A Chicago police officer was shot and killed in Avalon Park early Saturday, police said.

The officer had recently finished work when she was shot at about 1:42 a.m. in the 8100 block of South Blackstone Avenue, according to the Chicago police.

Another officer responded to an alert from the city’s gunshot detection system and found her wounded outside, police said. The responding officer put the wounded cop in a police vehicle and rushed her to the University of Chicago Medical Center, where she was pronounced dead.

No one was in custody, police said.

Police were investigating whether the slain officer’s gun was stolen, according to law enforcement sources.

She worked in the Calumet District and has been a member of the police department for three years. She hasn’t been identified.

“We ask you to keep the officer and her family in your prayers, as well as the men and women of the Chicago Police Department who sacrifice everything including their lives on the line for the city every day,” interim Police Supt. Eric Carter said at a news conference outside the hospital Saturday morning.