The accused gunman, identified as 24-year-old Deion Patterson, a former US Coast Guardsman whom Atlanta police had described earlier as “armed and dangerous,” was taken into custody north of the city in suburban Cobb County, several hours after the 12.30pm shooting at Northside Medical, authorities said.

The Cobb County Police Department announced the arrest on Twitter. No details were immediately provided.

Cobb County police earlier said Patterson was last spotted in images captured shortly after the shooting by a surveillance camera in the vicinity of the parking garage where the carjacked vehicle was later recovered, police said.

All five victims slain or wounded in the attack were women. Atlanta Police Chief Darin Schierbaum told a press conference that it was too early in the investigation to determine if they had been deliberately targeted, or if they were patients or employees.

The gunman arrived at the medical centre with his mother, the chief said, but she was not injured. Police said she was cooperating with investigators.

Little was immediately known about the suspect’s background.

The US Coast Guard said Patterson joined the guard in July 2018 and was discharged from active duty in January, after having last served as an electrician’s mate second class. No reason for his discharge was given.