The Chicago Tribune just unearthed a photo of Bernie Sanders getting arrested at a protest 50 years ago

The Chicago Tribune discovered a photo of Democratic presidential candidate Bernie Sanders getting arrested by Chicago police at a 1963 civil-rights rally in the city. The newspaper published the photo Saturday.

Sanders, a Vermont senator, was arrested, charged with resisting arrest, and found guilty of the crime. His punishment? A $25 fine.

At the time, he was a 21-year-old student at the University of Chicago.

"Bernie identified it himself," Tad Devine, a senior adviser to the campaign, told the Chicago Tribune. "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).'"

The black-and-white photo Sanders being taken by Chicago police toward a police wagon. An acetate negative of the photo was found in the Tribune's archives, said Marianne Mather, a Chicago Tribune photo editor. 

While at the university, Sanders was a leader of the Congress of Racial Equality, and multiple news accounts claim Sanders was leading protests about racial inequality, per the Tribune.