Thanks to Jimmy Kimmel, we've already seen Bernie Sanders' high school yearbook photos, but a new picture unearthed from the Chicago Tribune archives shows the Vermont senator in his rebellious college years. The Tribune's photo shows a young Sanders being dragged away between two Chicago policemen in front of what looks like a police barricade. More protestors are visible behind Sanders, and some guy smoking a cigarette is pictured to the trio's left.

Marianne Mather, a photo editor at the Tribune, said an acetate negative of the photo was discovered in the paper's archives, and Tad Devine, one of Sanders' senior advisers, said Sanders identified himself in a digital rendering of the photo: "He looked at it—he actually has his student ID from the University of Chicago in his wallet—and he said, 'Yes, that indeed is [me].'"

Information included with the negative indicates the photo was taken in August 1963 near South 73rd Street and Lowe Avenue in Englewood—Sanders would've been a 21-year-old University of Chicago student at the time. Court records confirm Sanders was arrested Aug. 12, 1963, and charged with resisting arrest; he was found guilty and fined $25, according to the Tribune. Video footage of the event has also been uncovered:

The photo comes to light at a time when at least one civil rights activist has openly questioned Sanders' alleged history of activism. "I was involved in the sit-ins, the freedom rides, the March on Washington, the march from Selma to Montgomery," Rep. John Lewis said during a press conference. "I never met him."

But as Bustle notes, Sanders does in fact have a rich history of activism, which includes attending the March on Washington, organizing sit-ins, and maintaining a strong voting record on civil rights issues. "His activism and when it occurred, as a young college student, set in motion the direction of his life," Devine told the Tribune. Dredging up the photo now is either coincidence or a brilliant strategy by Sanders' campaign. Either way, it sends a powerful message that the senator is a fighter.