Social media companies including Facebook and Elon Musk’s Twitter have been put on notice to halt “vile, repugnant” terror videos from Hamas, the Technology Secretary has said.

Following the terrorist organisation’s first attack on a music festival in Israel, Michelle Donelan  said she was shocked by the “horrific content on social media platforms” after the attacks.

Ms Donelan said she had been particularly alarmed by a “horrendous Facebook live [video] of a grandmother being slaughtered”.

Hamas terrorists murdered Blacha Levenson at Nir Oz kibbutz, less than a mile from Gaza, on Saturday before posting a clip of her bloodied corpse on her own Facebook page. The first her family knew of her death was the Facebook video.

Ms Donelan added that there was content on Twitter, now rebranded as X, that had been shared to millions of people which was “vile, repugnant content that would have a deeply disturbing impact on the British people, especially children if they saw that”.

The Technology Secretary told The Telegraph that while it was understandable technology companies had been taken by surprise by the attack, some posts were “not only illegal, but of course terrorism”, while officials had “continued to see” further examples of illegal posts.

On Wednesday, the Conservative minister held a video call with social media companies, including Meta, Twitter, Google, Snapchat and TikTok, asking them to explain their approach to the conflict.

The companies were asked to write to the Department for Science, Innovation and Technology with their crisis plan. She said they had submitted their responses late on Thursday.

Social media has been flooded by videos of violence from Hamas’s terror attack on Saturday and fighting in southern Israel and Gaza this week.

The social networks have also been battling to stem the spread of misinformation and doctored videos as well as tackling hate speech and antisemitism.

In the past couple of days, we’ve seen an increase in daily active users on @X in the conflict area, plus there have been more than 50 million posts globally focusing on the weekend’s terrorist attack on Israel by Hamas.

As the events continue to unfold rapidly, a cross-company…

— Safety (@Safety) October 10, 2023

Ms Donelan said while technology companies had assured her they understood the importance of tackling illegal posts, she had put them on notice.

She said: “If we see content continuing I will be calling them out… that is something we will be watching.

“Everybody wants to tackle this and there was a willingness from the tech companies to do that, we just have to make sure that now transpires.”

Ms Donelan was speaking as she revealed a total of £37m for new artificial intelligence projects ahead of the Government’s AI Safety Summit in November.

This included £5m in grant funding for early stage AI start-ups, including a business tackling clothing waste and a company developing AI for vineyards.

The European Commission has already launched an investigation into the response of X, which is owned by billionaire Mr Musk, to the crisis. Approached for comment, X sent an automated message stating: “Busy now, please check back later.”

In a post to the social network, X’s safety team previously said it had “actioned tens of thousands of posts for sharing graphic media, violent speech and hateful conduct”.

On Friday, a Meta spokesman said: “After the terrorist attacks by Hamas on Israel on Saturday, we quickly established a special operations center staffed with experts, including fluent Hebrew and Arabic speakers, to closely monitor and respond to this rapidly evolving situation.”

The company added in a blog post: “Hamas is banned from our platforms, and we remove praise and substantive support of them when we become aware of it, while continuing to allow social and political discourse.”

The UK is in the process of passing the Online Safety Bill, which will leave technology companies on the hook for fines worth billions of pounds if they systematically fail to stop the spread of terror posts or hate speech.