(03/06/07) NEWARK ? The 20-year-old man accused in a vehicle chase that led to the death of a Newark police officer pleaded not guilty in court Tuesday morning.

Investigators say police responding to reports of drag racing arrested William Rodriguez Saturday. According to police, Rodriquez managed to move his cuffed hands to the front of his body and take control of the patrol car in which he was being held. Police say during the high-speed chase that followed, Sergeant Tommaso Popolizio died in a vehicle accident.

Rodriguez is charged with one count of manslaughter. Prosecutors say he has a pending sentence in Mercer County for drug charges. According to prosecutors, upgraded charges of murder of a police officer will be sought if the case goes to a grand jury.

Related information: Newark cop dies after crash chasing carjacker suspect Friends, family begin saying goodbye to Newark cop killed on duty