LOWELL - Two brothers were killed in an overnight shooting on Andrews Street, according to police.

Keith Callahan, 35, was discovered at the scene, deceased, according to a news release from the Middlesex District Attorney's office. A second victim, identified as Joseph Callahan, 29, was transported to Lowell General Hospital where he later died. The two men were brothers.

Lowell police responded to a call for medical assistance at 105 Andrews St. around 2:35 a.m. Upon arrival, police discovered the two men suffering from apparent gunshot wounds.

Neighbors interviewed Sunday said they didn't hear or see the shooting and didn't know the victims. Police were gathered outside 103-107 Andrews St., a two-family home at the corner of Andrews and Otis streets, and at one point took two young men into a police car and drove away.

The young men were not handcuffed and did not appear to be suspects.

The Office of the Chief Medical Examiner will conduct autopsies to determine the cause and manner of each victim's death.

Lowell Police and Massachusetts State Police assigned to the District Attorney's Office are investigating the cause and circumstances of the shootings. There have been no arrests at this time, the DA's office said.

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