A former worker at Meta is being investigated by police over suspicions he downloaded about 30,000 private Facebook images.
The engineer is alleged to have designed a programme to access the pictures while avoiding internal security checks, UK court documents show.
A specialist detective from the Metropolitan Police's cybercrime unit has launched a criminal probe.
Meta, the company the owns Facebook, confirmed the suspected breach was discovered more than a year ago and said it referred the matter itself to police.
The US-based social media giant said affected users had been notified and the employee was sacked, while its security systems have also been upgraded.
The engineer, who lives in London, is on police bail while the investigation continues. A request to vary his bail conditions was recently granted by Highbury Magistrates' Court.
Court records state that the employee is accused of having "accessed and downloaded approximately 30,000 private images belonging to Facebook users whilst working for Meta" and that he created a special computer script in order to do so.
"Protecting user data is our top priority," said a Meta spokesperson.
"After discovering improper access by an employee over a year ago, we immediately terminated the individual, notified users, referred the matter to law enforcement and enhanced our security measures.
"We are co-operating with the ongoing investigation."
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In response to the investigation, a spokesperson for the Information Commissioner's Office (ICO) said: "We are aware of this incident. The ICO regularly engages with social media platforms, including Meta, regarding approaches to data protection to ensure that users rights and freedoms are being upheld.
"Social media users should be able to trust that their personal information is handled responsibly."
Meta - along with Google - last month suffered a landmark court defeat in the US after being found liable for a woman's social media addiction.
A jury in Los Angeles found Instagram, which is owned by Meta, and YouTube, which is owned by Google, were responsible for harm caused to the 20-year-old - awarding her $6m in damages.
Meta and Google both said they disagreed with the verdict and plan to appeal.
The decision was seen as a precedent that could inform hundreds more cases against social media companies for creating addictive algorithms.
In 2018, Facebook suffered a bug believed to have affected up to 6.8 million people and given third-party apps access to users photos.
Then in 2024 Meta, which also owns WhatsApp, was fined €91m by the Data Protection Commission in Ireland over the way millions of Facebook and Instagram user passwords had been inadvertently stored on internal systems, meaning they were not protected by encryption.
(c) Sky News 2026: Facebook worker investigated by police after download of 30,000 private images


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