SAN FRANCISCO (CBS SF / AP) — Hundreds of supporters of Bradley Manning — the Army private blamed for the largest leak of classified material in American history — marched through downtown San Francisco Saturday afternoon in a show of support for Manning.

As protesters marched down Market Street they chanted “Free Bradley Manning” and held up signs demanding his release.

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Dozens of police officers, many on motorcycles, kept the crowd on one side of the street.

Protesters stopped outside a Wells Fargo bank and heard from several speakers, including a brief statement made by Scott Olsen, the Marine Corps veteran who was badly injured during a clash between police and Occupy Oakland protests in October.

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The San Francisco protest comes on the same day the prosecution began presenting its case against Bradley in a military court in Maryland.

The 24-year-old Bradley is accused of leaking hundreds of thousands of sensitive items.

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