The Justice Department won't charge two white police officers in the death of Alton Sterling whose fatal shooting was captured on cellphone video, fueling wide-spread protests.

Police arrested three suspects and were seeking a possible fourth suspect accused of stealing several handguns as part of what authorities Tuesday described as "substantial, credible threat" to harm police officers in the Baton Rouge area.

A search warrant from Baton Rouge police says officers saw "the butt of a gun" in Alton Sterling's pocket during the arrest and that he tried "to reach for the gun from his pocket."