Several students walked out of their Stanford University graduation ceremony as Google CEO Sundar Pichai took the stage to deliver a keynote address.

Video filmed by the BBC shows dozens of people protesting against the company's controversial work with the US government. One sign read "ICE spies with Google AI".

This follows other recent campus protests against tech leaders, but those have largely focused on artificial intelligence and concerns about jobs.

Pichai largely sidestepped the issue of AI in his remarks, though he appeared to make light of the expected protests. "People thought it would be really difficult for me," he said. "It is the last two letters of my last name, after all."

Pichai, a Stanford alum, did not respond to the BBC's request for comment.

The exact number of students who walked out of the graduation remains unclear, though SFGate estimated it was around 200.

It is also not clear if all the students who left were motivated by the same cause, as some were seen waving Palestinian flags.

The protests against graduation speakers in the US this year showed the broader unease on campuses about AI: Speakers who mention AI are increasingly being met with hostility from students.

"I know what many of you are feeling about that. I can hear you," Schmidt told graduates as jeers rang out at the venue during remarks comparing today's AI boom to the rise of computers four decades ago.

Gloria Caulfield, a real estate executive, saw a similar reception at the University of Central Florida: "The rise of artificial intelligence is the next industrial revolution," she said as the crowd booed.

At the mention of AI at Middle Tennessee State University commencement, Scott Borchetta, CEO of Big Machine Records, was also met with jeers.

His response to graduates: "Deal with it, like I said, it's a tool."

Additional reporting by Lily Jamali