BATON ROUGE, La. — The man accused of killing a Baton Rouge civil rights activist and dumping her body in the trunk of her own car has been indicted on a second-degree murder charge.

An East Baton Rouge Parish grand jury handed up the indictment against 38-year-old Ronn Bell on Wednesday. He faces a mandatory life sentence in prison if convicted of the July slaying of Sadie Roberts-Joseph. Preliminary autopsy results showed she was strangled before being shoved into the trunk.

Bell was a tenant in a rental property owned by the 75-year-old victim and was behind on about $1,200 in rent.

Police have said a "solid motive" remains under investigation but investigators don't believe Roberts-Joseph's death was a hate crime or related to her community activist role.

baton rouge activist sadie roberts johnson murder suspect

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