LOWELL -- The double-killing of the sons of a retired Lowell police sergeant early Sunday morning in the normally quiet Sacred Heart neighborhood was a case of mistaken identity, The Sun has learned.
"You are 100 percent correct," said a source who has been briefed on the case when asked by The Sun if the suspect had entered the wrong residence at 105 Andrews St. "This is a case of mistaken identity."
Investigators late Sunday night released a sketch of a 25- to 35-year-old man who is described as a person of interest in connection with the shooting deaths of brothers Keith and Joseph Callahan.
Keith Callahan, 35, and Joseph Callahan, 29, are sons of retired Lowell police Sgt. Richard Callahan.
Details are still sketchy, but sources told The Sun the shootings occurred in the upstairs apartment occupied by one of the brothers.
According to several sources, the suspect broke down a door to the apartment and encountered the brothers and one of their wives. The suspect was yelling that he was looking for someone. At gunpoint, he herded the brothers and the woman into a bathroom, where he told them to remain there while he looked around. The sources said the Callahans expressed concern about a young child about 11, who was sleeping on a nearby couch. At that point, the suspect opened fire, possibly after an altercation with the brothers, the sources said.
"It's remarkable the woman wasn't hurt," one source said.
Police have been investigating the deaths since Sunday about 2:30 a.m., when officers were called to 105 Andrews St., for what was initially a call requesting medical assistance.
Officers arrived to find Keith Callahan dead from gunshot wounds, and Joseph Callahan suffering from a gunshot wound that would claim his life after he was taken to Lowell General Hospital.
Police initially released little further information, but Sunday night prosecutors released a sketch of a man described as a light-skinned Asian male, 25 to 35 years-old, about 5-feet, 6-inches tall, with a thin build.
The individual being sought wore his hair in a ponytail and had a mustache and a goatee that falls about a half inch below his chin, according to prosecutors. He was last seen wearing a white T-shirt and jeans.
Anyone who believes they may know this man's identity is asked to call Lowell police at 978-937-3200 or use the Crimestoppers anonymous tip line at 978-459-TIPS (8477). Anyone with information can also call state police detectives assigned to the office of District Attorney Marian Ryan by calling 781-897-6600.
Follow Scott on Twitter @cscottlowellsun.