A pro-Palestinian protest by Microsoft employees interrupted the company’s 50th anniversary celebration early on Saturday, the latest backlash over the tech industry’s work to supply artificial intelligence technology to the Israeli military.

The protest began as Microsoft AI CEO Mustafa Suleyman was presenting product updates and a long-term vision for the company’s AI assistant product, Copilot, to an audience that included Microsoft co-founder Bill Gates and former CEO Steve Ballmer.