Sir Paul McCartney joined tens of thousands of people at the March For Our Lives rally in New York City on Saturday.
He explained to CNN that it was important for him to come out to support the people.
The former Beatle wore a shirt that read, "We can end gun violence," and spoke of losing John Lennon to gun violence, near where they marched on Saturday.
"One of my best friends was killed in gun violence right around here," McCartney said, "so it's important to me."
John Lennon was shot and killed while walking with his wife in Manhattan in 1980.
Hundreds of thousands of teenagers and their supporters rallied in the nation's capital and cities across America on Saturday to press for gun control in one of the biggest youth protests since the Vietnam era.
The Associated Press contributed to this report.
