Tech stocks tumbled for the second day in a row as concerns rise over the hundreds of billions of dollars firms are investing in artificial intelligence (AI).

Shares in Intel plummeted by 28% on Friday, while Google owner Alphabet saw its stock price continue to fall another 1.4% after a 12% plunge on Thursday.

Other tech stocks, including Reddit and Amazon also fell, while the Nasdaq index of the largest tech firms listed in the US, ended October with its worst monthly slide since March 2025.

While tech firms are spending big on AI, their earnings are not always meeting analysts' expectations, spooking investors and creating fears of an AI bubble.

Major tech companies have ramped up artificial intelligence spending, with Meta, Alphabet, Oracle, Amazon, and Microsoft committing to spending $800bn between them in 2026.

Alphabet's stock market value fell sharply on Thursday, taking more than $500bn (£374bn) off its market value after it revealed the AI summaries it now provides as the top answer to search queries were affecting its core search advertising revenue.

At the same time, Alphabet expects to spend up to $205bn this year on investments, almost entirely related to AI.

The bigger losses on Friday were elsewhere however, with Intel shedding more than $130bn in value.

The chip maker said it planned to increase spending on AI despite weaker demand for computers, a major source of demand for its micro-processors.

On Thursday, Intel's finance chief David Zinsner said the firm did not expect to bring in more cash than it spent this year and forecast lower-than-expected revenue for its fourth quarter.

"Looking ahead, we see the PC slowdown continuing at least through the first half of next year," he said in the chip maker's third quarter earnings report.

In the earnings call, he said the firm had significantly ramped up investment in equipment in the third quarter and expected that to be "even more significant" in the following three months.

Amazon on Thursday revealed it had also spent more cash than it was making, and that spending had increased six-fold over the span of three months.

The company has committed to spending $220bn this year, putting the money towards investments such as AI data centres, network equipment, and servers.

Amazon shares recovered some overnight losses, but were still down by 1.4% at the end of Friday trading.

Reddit stock plunged by 29%, after the social media platform revealed weaker-than-expected daily user figures and warned that Google's growing AI-driven search was hurting referral traffic.

Stock in online game platform Roblox also fell, down by 18%, as its daily active user numbers dropped.

Several major tech firms have reported earnings this week, including Microsoft, and analysts said there were questions about the payout from the huge investments in AI.

Chris Low, from investment management firm FHN Financial, said the bulk of what was happening in the stock market was in reaction to some of the biggest tech players such as Amazon and Google.

He told Reuters the companies were "showing some pretty significant growing pains as they aggressively pursue the AI build-out".

"The thinking is that these signs suggest that the entire sector is going to slow down."

Many analysts have been debating the possibility of an AI bubble in the stock market.

The worry is that some tech firms will not be able to justify their sky-high valuations because the cost of building AI data centres and developing the software will end up being greater than the money they can make from it.

Kathleen Brookes, research director at trading firm XTB, said there have been many ups and downs in AI trade in recent months.

"Investors have turned ruthless, punishing any signs of disappointment in [third quarter] earnings," she said.

"The AI trade has had a good run in recent years, but now investors want payback, and companies like Alphabet and Intel are in the crosshairs."

However, stock market values for many of these companies remain well above where they were a year ago.

While the Nasdaq closed 2.8% lower, it is up 7.8% over the last year. Similarly Amazon is up nearly 8% over the past 12 months, while Alphabet is down 1.3%.

Brookes noted that November is typically a strong month for stocks.

"If we see AI stocks continue to struggle in the coming days, it could suggest the AI trade is past its peak, and investors will be looking for a new theme to drive markets," she said.

Google value plunges by $500bn as its own AI search hits ad sales

Binance, the world's largest cryptocurrency exchange, says it has frozen around half of the funds stolen in a "complex" hack, after $6.3bn (£4.7bn) was accessed in what is believed to be a record heist.

The firm said $3bn of its stolen digital assets had been secured - but many were still in the hands of unidentified hackers. It initially thought an engineer's laptop had been compromised, allowing unauthorised withdrawals, but later said the attack was wider.

Several analytics firms have linked the hack, which eclipses a $1.5bn (£1.12bn) heist on the Bybit exchange in 2025, to a North Korean hacking unit.

The US Secret Service said it was "working around the clock" "to identify, freeze, trace, and recover" stolen funds.

America's lead federal agency for investigating financial crimes added that it would "identify the cyber criminals responsible and bring them to justice", while Binance also said it was working with the FBI.

While Binance said its US-facing exchange was unaffected, the US would still have jurisdiction to investigate the hack and help track down stolen funds - an effort which generally involves a global law enforcement effort.

The hack also involved some US-linked assets, such as stablecoins Tether and Circle – cryptocurrencies pegged to the dollar.

Binance told its users "your money is safe, and we're covering every loss".

It had initially suspended all deposits and withdrawals - but then said in an update that "deposits remain unaffected".

Who could be behind the Binance hack and what we know so far

Binance's co-CEO Richard Teng said: "This was not carried out by one person. Our initial investigation suggested that the security incident may have involved a compromised laptop, however our subsequent investigation has uncovered additional points of breach."

Teng also describes how the hackers used "a self-destruct mechanism that destroyed tooling and traces as they went, making it more difficult for us to trace and investigate".

Initially, the company had indicated the breach "may have started with a compromised DevOps engineer's laptop" but later statements have pointed to a broader breach.

In a later update, the firm set it had "set aside" more than $6.34B in company funds to cover the stolen assets and was "actively buying" a range of crypto tokens.

The Binance hack spooked cryptocurrency markets on Friday. The price of Bitcoin was down 5% to $76,800 in Friday afternoon trading in New York.

Cryptocurrency exchange Coinbase was down 12% as investors also reacted to earnings results in which the firm reported revenue slightly below expectations. Robinhood, a financial services company that trades in cryptocurrency, was down 7.8%.

Binance, which was founded in China in 2017, allows users to trade digital assets and is estimated to have more than 300 million registered users worldwide.

The company said in 2024 that it had more than $160bn in assets under its custody.

A lot of the fear right now from Binance users - and the crypto industry at large - is whether or not Binance will actually be capable of covering this enormous financial loss.

The company has said repeatedly that customer funds will be covered and that the firm is strong enough to weather the storm.

But crypto history watchers have been pointing out online that this is exactly the kind of message that FTX CEO Sam Bankman-Fried gave before his crypto exchange collapsed in 2022, leading to huge losses for customers and the industry.

Several experts have warned customers not to regard Binance's promise to cover losses as legally binding and said they may need to pursue litigation to recover them.

Daniel Tunkel, of the London-based Edwin Coe law firm, said that would "come down to what [customers] have been promised in their contracts", and "where Binance can be sued for non-performance, if it comes to it".

Binance has been subject of regulatory scrutiny around the world.

Meanwhile, AI-powered investigations company TRM Labs said that several elements of the attack resembled earlier North Korean-linked incidents, including the Bybit hack.

In the last five years the crypto industry has been beset by enormous losses from hackers.

In nearly all cases investigators have blamed hackers from North Korea, pointing to the infamous Lazarus Group - also know as TraderTraitor. The names refer to clusters of cyber criminals accused of working directly for the regime.

Chainalysis, a crypto analytics firm, said it had "high confidence" that a North Korean is linked to the hack.

North Korea is an impoverished country with very little industry and heavy international sanctions and experts say the regime uses cyber crime as a way to bring money in.

North Korea has always denied this, but the wealth of evidence from cryptocurrency flow analysis and insider interviews from defectors is compelling.

It makes North Korea likely to be the only nation that uses hacking as a way to raise public funds.

AI gold rush draws crypto firms away from Bitcoin

Meet the crypto billionaires building a world where money buys you a vote

There is no end in sight for the drivers of illegal mining, while police action appears ineffective

C ora Bailey has been encountering illegal miners ever since she first started treating injured animals in the townships around Roodepoort, west of Johannesburg, in 1991. But as the price of gold has soared, so too has activity in the abandoned mine shafts that mark the area.

In late September, dozens of zama zamas – the name given to illegal miners in South Africa , meaning roughly "to take a chance" in Zulu – arrived to dig for gold across the dirt road from her charity, Claw (Community Led Animal Welfare).

Soon, they were taking water for their panning and processing from the organisation's two 25,000-litre water tanks, which are filled irregularly by the city government for the 100 or so rescued and injured animals on site.

"We've asked them really nicely and haven't ever refused them water to drink … But, for the first time ever, we closed the gate at 12 [midday], because we literally had about two buckets of water left," Bailey said in mid-October.

Police told her that the scale of the illegal mining was too big for them to do anything about, she said at the time. About a week later, officers sheared away the grass that had partly hidden the zama zamas . But within a few days a smaller group had returned, although Bailey said they were now taking Claw's water only for drinking.

South Africa's police regularly trumpet their success in tackling illegal mining. On 19 October, they said they had arrested 71 suspected zama zamas across the country in the previous week.

However, researchers put the number of illegal miners in the tens of thousands. In 2019, Marcena Hunter, a researcher at the Global Initiative against Transnational Organised Crime, estimated that a tenth of South Africa's gold production , worth about $1bn, was being exported illegally .

Police operations have also led to tragedy. In 2025, 93 bodies were pulled from a mine shaft in Stilfontein , after officers blocked food and water from being delivered underground.

Meanwhile, there is no end in sight to the dynamics driving illegal mining, including the high price of gold, poverty, unemployment, corrupt politicians and police profiting, and the failure of mining companies to fulfil their legal obligation to seal mining shafts when they cease operating.

South Africa's modern history is tied to mining. In 1884, gold was found on a farm, sparking a gold rush that led to the creation of Johannesburg. Gold production peaked in the 1970s , but South Africa was the world's largest producer, a title it held for more than a century, until 2007.

In 2009, Morris Viljoen, a geology professor at the University of the Witwatersrand, estimated that the reef that gave the university its name had produced more than a third of the gold ever mined globally. Claw is housed in the old offices of the Durban Deep mine, which shut at the turn of the century, having once lent its name to an Elton John song .

The city government claims there is still 40,000 tonnes of gold underground in the region. But, with the remainder lying ever deeper, the costs of recovering it have risen.

Mining companies are supposed to seal up old mine shafts and rehabilitate the environment around them. However, in 2025 there were "6,100 derelict and ownerless mines and 1,170 unsafe mine openings", the mining minister, Gwede Mantashe, said in response to a parliamentary question.

Zama zamas have stepped into those voids left in the earth. While there is no comprehensive data on them, experts agree that a majority are from neighbouring countries, principally Lesotho, Mozambique and Zimbabwe.

The skyline south of Johannesburg is punctuated by the pale yellow ridges of mine dumps. Increasingly, the ground is also caving open.

For politicians seeking votes in local elections on 4 November, the culprit is clear: illegal miners. In May, Kenny Kunene, the Johannesburg council member responsible for transport, took journalists on a tour of sinkholes that he claimed were the fault of zama zamas , including a section of Wemmer Pan Road that had completely collapsed .

The road was once the main artery linking the city's central business district to the south-eastern suburbs. In one section it has completely disappeared, now raw earth pitted with the holes where illegal miners have been digging.

However, when it comes to sinkholes, experts say zama zamas are being scapegoated.

Rosalind Morris, an anthropology professor at Columbia University, who has worked extensively with illegal miners, noted that the porous dolomitic rock to Johannesburg's south and west becomes unstable when water is removed.

"The biggest culprit of sinkholes in South Africa is formal industrial mining, which dewaters at a scale of hundreds of millions of gallons of water removed from underground every day," she said.

"There are areas where there is a lot of residual gold, which are being very intensely mined by zama zamas , and some of that definitely causes structural collapse, there's no doubt about it. But the idea that this was invented or caused for the first time by zama zamas is completely fallacious."

Zama zamas are also frequently blamed for violence in mining areas, including a September mass shooting in Wedela township, west of Johannesburg. However, David van Wyk, the lead researcher at Bench Marks Foundation, said culpability laid with the often-feuding gangs that controlled access to the shafts.

"The guys working in the mine are actually super-exploited cheap labour … The guys with the guns are the guys who take the gold," he said. "They don't go underground."

In Khutsong, about 50 miles (80km) west of Johannesburg, illegal miners, local and foreign, kept the township afloat, said Vusi Cele, the youth secretary for the local branch of Mining Affected Communities United in Action, a campaign group that advocates for "artisanal miners" to be granted mining licences. "Without those rents, it's a ghost town," he said.

While Cele, 33, currently hustles above ground selling mobile phone covers and screen protectors, he said he too would mine if he could get a licence. "On the surface there's peanuts," he said. "Underground there's money."

At just 14, Zhang Shaoqing's prowess with AI tools means he could easily be included in the ranks of the new wave of "super students" but it's a description he balks at.

"Daring to imagine and daring to try is encouraging, but it's also a kind of pressure; it's as if I'm not a good student unless I've built something," said the ninth-grader at Wuxi Dipont School of Arts and Science in Jiangsu province.

"I don't want to be defined as a 'super student.' I would rather be seen as an ordinary student who has stayed passionate about one field for a long time," he added.

His mother Liu Liwei, who has encouraged his development and interests, is also uncomfortable with the super student label, which has recently gained online traction.

Many youngsters involved in sophisticated technology projects are not necessarily way ahead of others, but have benefited from opportunities, guidance and supportive environments, she said. "I always remind him not to think he is better than others. He has simply received opportunities that many students may not have had," said Liu.

From developing artificial intelligence tools for schools to creating digital content, a growing number of Chinese teenagers are moving from technology users to creators, offering a glimpse into how they are exploring opportunities and challenges in the AI era.

In recent years, Chinese school students have begun participating in AI competitions, open-source communities and industry-linked innovation programs once mainly associated with university students and professionals.

Tencent Youth Tech Training Camp, launched in 2016, has attracted more than 900,000 users to its platform, partnered with over 2,000 schools and accumulated more than 40,000 works as of September 2026.

Dong Xinye, deputy director of the Youth Innovation Education Center at Shenzhen InnoX Academy, an education program that aims to nurture innovative talent for the AI era through project-based learning, said teenagers' participation in AI and innovation programs has grown significantly in recent years.

"What was once a niche interest among a small number of technology enthusiasts has gradually become a mainstream way for young people to explore the world," said Dong.