REVERE – A fourth local youth was indicted Thursday by a grand jury in connection with the murder of Revere Police Officer Daniel Talbot.James Heang, 17, who had been held since Oct. 1 on a charge of possession of an illegal stun gun, was additionally charged Thursday with being an accessory after the fact to Talbot’s murder and unlawfully carrying a firearm.”His role is believed to be confined to events after Talbot’s death,” Suffolk County District Attorney spokesman Jake Wark said Thursday.Heang had been held in custody since Oct. 1, when his arrest for unlawful possession of a stun gun triggered the revocation of his bail on an unrelated case. He is represented by attorney Willie Davis.Heang’s indictment is the product of a Suffolk County grand jury investigation into the Sept. 29 shooting death of Talbot. Over 25 witnesses testified before the grand jury. Along with Heang, three other people already arrested in connection with Talbot’s death have since been indicted by a grand jury.”These indictments reflect a painstakingly thorough investigation by Suffolk homicide prosecutors and State Police homicide detectives with the support of Revere Police,” Suffolk District Attorney Daniel Conley said. “This does not signify the end of the investigation – this is merely one further step in our ongoing efforts to hold accountable those responsible for Officer Talbot’s murder.”Superior Court arraignments for each of the defendants are currently being scheduled, Conley said. They are expected sometime next week.One of them, Gia Nagy, 17, of Revere, was arrested last weekend and charged with being an accessory after the fact to murder. Prosecutors said she attempted to destroy and hide the murder weapon. Nagy pleaded not guilty to the charge.Police charged Robert Iacoviello, 20, of Revere on Nov. 13 with shooting Talbot and arrested and charged Derek Lodie, 17, also of Revere, days after the shooting and charged him with being an accessory before the fact to murder.Both men pleaded not guilty to the charges. Prosecutors say Lodie traded words with Talbot, three other off-duty police officers and Talbot’s fiancé near the high school bleachers at about 2 a.m. on Sept. 29.They said Lodie then called several people to meet him at the high school, including Iacoviello who, they said, fired a shot that struck Talbot in the head. Prosecutors said Iacoviello fled and hid in Nagy’s Eastern Avenue home. They said Nagy helped dismantle the handgun used in the shooting and dropped the pieces into drains along Cushman Avenue.Police interest in Iacoviello and Heang surfaced days after Talbot’s death when heavily armed officers searched their homes and arrested them on charges unrelated to the Talbot murder.