NEW KENSINGTON, Pa. (AP) — The manhunt for a suspect and a person of interest in the fatal shooting of a rookie police officer in Pennsylvania is into its fourth day.

Pennsylvania state police have issued an arrest warrant for 29-year-old Rahmael Sal Holt. He's accused of killing New Kensington Officer Brian Shaw during a traffic stop Friday night. Holt faces charges of murder and murder of a police officer.

Authorities say the 25-year-old rookie was shot in the chest while chasing Holt on foot.

Authorities are also trying to find Lisa Harrington as a person of interest. It's not clear how she's connected to the case.

Shaw had served as a part-time officer in three other towns before joining the New Kensington force full time in June.

New Kensington is about 18 miles (29 kilometers) northeast of Pittsburgh.

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