A Dorchester man once charged as an accessory to the murder last year of Gregory Phillips in Allston was held without bail today after a grand jury investigation identified him as the 24-year-old victim’s killer, Suffolk County District Attorney Daniel F. Conley said.

COREY PATTERSON (D.O.B. 11/5/86) was held without bail today on a single count of first-degree murder and five additional counts of assault and battery on the Boston Police officers who extricated him from the vehicle in which he tried to escape in the early morning hours of Nov. 8. Those charges represent additional evidence developed in the course of a seven-month investigation led by members of Conley’s Homicide Unit in the Suffolk County Grand Jury and Boston Police homicide detectives on the street.

Assistant District attorney Gretchen Lundgren told Clerk Magistrate Gary D. Wilson that Phillips – a West Roxbury resident who worked at Boston University – was with his roommate and two female friends when he left a birthday party at The Kells shortly after 2:00 a.m. on Nov. 8.

“As the bar was emptying out, the defendant began speaking with a female friend of the victim and began speaking with her and making rude comments,” Lundgren said. “Mr. Phillips’ roommate asked the defendant to leave her alone and a verbal argument ensued. Mr. Phillips’ roommate asked the defendant to take the argument around the corner.”

As Phillips’ roommate, Patterson, and a group of Patterson’s friends and relatives headed toward the corner of Brighton and Harvard avenues, however, Patterson allegedly punched Phillips’ roommate in the back of the head, prompting Phillips to intervene.

“Coming to his friend’s aid, Mr. Phillips, unarmed, approached the defendant and the two became engaged in a physical altercation,” Lundgren said. “At that point, one of Mr. Phillips’ friends screamed, ‘He’s got a knife,’ referring to the defendant. As Mr. Phillips backed away from the defendant, this friend saw the defendant punch Mr. Phillips.”

The defendant fled, Lundgren said, and Phillips staggered across the street with blood beginning to soak through his shirt from a stab wound to his chest that would ultimately prove fatal. Phillips died at Beth Israel Deaconess Medical Center of a stab wound to his heart.

Patterson and his group drove away from the area in a Lincoln sedan but returned, Lundgren said, when Patterson said he needed to retrieve something.

“He further stated that people had seen him throw the poker under a car and he needed to get it because it had his prints on it,” the prosecutor told the court.

As Patterson’s cousin drove back toward the area, Patterson allegedly jumped from the car, reached beneath another vehicle, and retrieved a folding knife.

A Boston Police detective securing the scene observed this action and went to stop Patterson’s car while calling for backup. Patterson allegedly struggled violently with the officers, kicking and punching them, before being removed from the car and restrained for transport to Boston Police headquarters.

Patterson was arraigned the next day as an accessory to Phillips’ murder. During the grand jury investigation, police and prosecutors developed additional information and statements supporting the murder charge, and Conley’s office approved a warrant charging him with that offense on Feb. 16. He has remained in custody since his initial arrest.

Kara Hayes is the victim-witness advocate assigned to the case. Patterson is represented by attorney Keith Halpern. His trial was tentatively scheduled for July 5, 2011, and he will return to court on Sept. 9.