Tucson police say a 13-year-old boy faces a murder charge.

Police say a 15-year-old accused of taking part in the Jan. 24 killing of 32-year-old Terrance R. Ross near North Sixth Avenue was shot and killed Jan. 28 near East Wetmore Road.

A 13-year-old boy who was already being held in Pima County Juvenile Detention Center now faces a murder charge related to Ross’s killing.

The 13-year-old also faces charges including armed robbery and aggravated robbery. He had been arrested Jan. 31 on unrelated charges.

No arrests have been made in the 15-year-old’s killing.

Those with information should call 88-CRIME.