Filmmakers in Chicago making a documentary about 1963 school segregation protests appear to have identified 53-year-old footage of a young Bernie Sanders being arrested during a demonstration, the group making the film said in a Monday blog post. Here’s the clip:

Sanders hasn’t commented on whether he’s seen the footage or believes it depicts his arrest.

The Vermont senator studied at the University of Chicago from 1960 to 1964 and is known to have been arrested during a segregation protest on Aug. 12, 1963 in the same area that the footage was taken. (Here’s a Mother Jones article about Sanders’ participation in Chicago civil rights activism.)

The group making the documentary is called Kartemquin Films; the project in progress, called ’63 Boycott, is a then-and-now look at a boycott of Chicago public schools in which “more than 200,000 Chicagoans, mostly students, marched to protest the segregationist policies of CPS Superintendent Benjamin Willis.” Willis had refused to integrate Chicago schools despite overcrowding in black classrooms, instead assigning many black students to attend classes in aluminum trailers that became known as “Willis Wagons.” The protest at which Sanders was arrested, Kartemquin writes, was in the Englewood neighborhood at a site at which “Chicago Public Schools was planning to build an entire school out of Willis Wagons.”