By Jessica Derschowitz
March 24, 2018 at 01:07 PM EDT

Paul McCartney was among those who came out in New York on Saturday for one of the March For Our Lives rallies happening across the country protesting gun violence, and referenced a personal reason for supporting the cause.

Speaking to CNN’s Jason Carroll, the legendary musician and activist noted, “One of my best friends was killed in gun violence, right around here, so it’s important to me.”

McCartney was referring to his Beatles bandmate John Lennon, who was shot and killed outside his New York apartment building on Dec. 8, 1980, not far from where protestors gathered Saturday to begin their route for the march.

When asked if change could happen at the legislative level, McCartney, who wore a shirt that said “We Can End Gun Violence,” told Carroll, “I’m like everyone, I don’t know. But this is what we can do, so I’m here to do it.”

Many other stars have also shared their support on social media or are taking part in Saturday’s marches. See more of their messages here.