ST. LOUIS (AP) — A St. Louis house fire has killed three children, seriously injured a man who tried to rescue them and forced several people to jump from the home’s upper floor.

The fire started around 4 a.m. Sunday in the northern part of the city. Fire Captain Greg Favre says seven people were able to escape, with some jumping and others forced out the front door.

Favre says the child victims ranged in age from 10 months to 6 years. The hospitalized man was injured when he tried go back inside the home for the children but was pushed back by the heat.

Authorities believe the fire started with a space heater.