St. Louis police say they've identified a 25-year-old black man shot to death by two white police officers not far from a suburb where a police killing of a black 18-year-old touched off racial upheaval.

Police say Kajieme Powell died at the scene of Tuesday's shooting by two police officers.

Police say Powell twice visited a convenience store minutes apart, stealing items both times before he was reported acting erratically while pacing the street, a knife in his hand.

Authorities say the responding officers shot him after he refused to drop the knife and moved toward the officers, telling them "Shoot me now. Kill me now."

The shooting came 10 days after Michael Brown was shot and killed in Ferguson by a white police officer.

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