A Sandy Springs man walked into the city’s police headquarters Wednesday afternoon and told officers he was turning himself in because he had assaulted his girlfriend and she was unresponsive, officials said.

Mamadi Tambajang surrendered at about 12:45 p.m., Sandy Springs police said. Patrol units then went to Tambajang’s apartment, where officers found a woman dead, according to police.

No information was released about how or when the woman died, and she has not been publicly identified. Jail records indicate the fatal incident may have taken place Monday.

Detectives executed search warrants at Tambajang’s apartment as well as his mother’s apartment, police said. No other details were released, but police said the investigation remains open.

Tambajang was taken into custody on charges of murder and aggravated assault. He was booked into the Fulton County Jail on Wednesday and remains there without bond.