An allegedly drunk driver rammed his car into the back of a patrol car on Thursday and then allegedly assaulted and threatened a police officer.

Stephen Biernacki, 46, was arrested after he drove into a patrol car at 3:36 p.m. on Route 539, police said Sunday. Patrolman Edward McNally, who was driving the patrol car, was injured, police said.

After he was taken to police headquarters for processing, Biernacki became irate and aggressive, police said. He hit and threatened to kill the officer who was processing him, according to a news release. The officer was not injured.

Police charged Biernacki with driving while intoxicated, making terroristic threats, resisting arrest, and aggravated assault on police. He was transported to Ocean County Jail, Toms River, and held in default of $50,000 bail.