A photo of Democratic presidential candidate Bernie Sanders has emerged from the Chicago Tribune archives showing the then 21-year-old student being arrested at a civil rights protest.

The image could help boost Sanders’ presidential run by addressing recent questions over his participation in civil rights campaigns and his commitment to issues important to black Americans.

This man, arrested in Chicago in 1963, is aiming for a win in the Nevada caucuses today https://t.co/nGE9i0xgl0pic.twitter.com/Y0Im1c7LEs — Chicago Tribune (@chicagotribune) February 20, 2016

"Bernie identified it himself," Tad Devine, senior adviser to Sanders’ campaign, told the Chicago Tribune of the newly discovered image.

Sanders was arrested on August 12, 1963, during a school segregation protest in Chicago’s Englewood neighborhood and charged with resisting arrest. He was found guilty and fined $25.

Footage of the 1963 arrest, entitled Is this Bernie Sanders being arrested? was uploaded earlier this week by Kartemquin Films.

The arrest photo could help boost Sanders at a pivotal point on the campaign trail, as the Democratic candidates fight it out in the Nevada caucus on Saturday.

If this photo of @BernieSanders being arrested in a '63 civil rights protest goes viral, it might change things. https://t.co/bnePSZwi1j — Chris Johnson (@chrisjohnson82) February 20, 2016

Normally a photo of you getting arrested coming out on the day of an election would be a bad thing... https://t.co/j9bIMFDH41 — Ryan Teague Beckwith (@ryanbeckwith) February 20, 2016

There's no question the Bernie Sanders arrest photo is pretty cool.https://t.co/w6CQIII4pppic.twitter.com/zhWZhtdYlw — Paul Lewis (@PaulLewis) February 20, 2016

Sanders’ activist past has been under scrutiny after questions arose about another photo that appeared to show Sanders addressing students at a 1962 campus sit-in. Several alumni claimed the man was another student, now deceased.

Classmates pointed out it's a man named Bruce Rappaport. The photo is still on official @BernieSanders tumblr page. pic.twitter.com/Aub9xDoQ6f — Randy Renstrom (@RandyRenstrom) February 12, 2016

However, the photographer who took the photo, Danny Lyon, confirmed the man in question was Sanders.

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