A poster of Huey P Newton, minister of defence for the Black Panthers, is estimated at $8,000-12,000 ahead of a sale at PBA Galleries in San Francisco on June 19.
It shows him seated in a wicker chair, holding a harpoon and a rifle, with a quote below that reads: "The racist dog policemen must withdraw immediately from our communities, cease their wanton murder and brutality and torture of black people, or face the wrath of the armed people."
Newton was a co-founder of the party, which became known as the militant arm of the civil rights movement in America.
He had a reputation for violence and was tried for murder on a number of occasions. He was shot dead by a Black Guerilla Family member in 1989.
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