A Roxbury man was held without bail today on a murder charge stemming from the shooting death of 28-year-old Senai Jamaal Williams in a Homestead Street apartment building yesterday afternoon, Suffolk County District Attorney Daniel F. Conley said.

JAMES ALLEN (D.O.B. 8/30/88) is charged with murder, unlawful possession of a firearm, and unlawfully carrying a loaded firearm. He was arraigned in Roxbury District Court following his arrest last night by Boston Police homicide detectives amid a fast-breaking investigation into Williams’ death.

Assistant District Attorney Jennifer Hickman of Conley’s Homicide Unit told the court that the incident began with an altercation inside a hallway at 20 Homestead St. at about 4:30. Neither Williams nor Allen was involved in that altercation, prosecutors said.

As a result of the altercation, Allen, Williams and another man came to the hallway. The conflict spilled outside and continued, prosecutors say, until Williams produced a knife and suffered a fatal gunshot wound to the stomach, allegedly at Allen’s hand.

Williams was transported to Boston Medical Center, where he died of his injuries.

All parties fled the scene. Armed with a description of the alleged gunman and additional information developed by Boston Police, Allen was tracked to the Bromley Heath housing development and placed under arrest.

Roxbury District Court Judge Sidney Weingarten ordered Allen to return to court on Dec. 15 with attorney James Budreau. Katherine Moran is the DA’s assigned victim-witness advocate.