Homicide detectives are investigating after three young children were found dead in an apartment fire late Friday in Gary, Indiana.

Crews responded at 11:26 p.m. to the blaze at a unit of the Oak Knoll Renaissance apartment complex in the 4400 block of West 23rd Court, according to the Gary Fire Department.

A woman jumped from a second-story window to escape the flames and heavy smoke, fire officials said.

Once the fire was brought under control nearly an hour later, firefighters found two of her children dead in separate beds on the second floor, and a third child on a staircase, fire officials said.

The Lake County coroner’s office identified a girl and boy as 4-year-old Alaya Pickens and 5-year-old Jayden Mitchell. They lived in the 3500 block of West 20th Avenue in Gary. On Monday, the coroner’s office identified the third child, a cousin, as a 2-year-old girl named Yaleah Cohen, who lived in the apartment where she died.

The woman was taken to a hospital with burns and was expected to survive, according to police and fire officials.

The Lake County Metro Homicide Unit and the Indiana State Fire Marshal are among the agencies investigating the fire, according to police and the coroner’s office. The cause is under investigation.