The City of Erie Fire and Police Departments are investigating an apartment fire that claimed the life of two small children and left a third child, a 5-month-old, fighting for her life.

According to Chief Erie Fire Marshal Don Sauer, a neighbor, Brandon Lewis, first spotted the flames shooting from the second-floor apartment of a home at 535 and a half East 26th Street just before 4:30 p.m. Sunday.

Lewis called for help, jumped over a fence, kicked in the door and attempted to save the children, but the smoke was too thick.

With reports of possible entrapment, Erie firefighters responded to the scene quickly and crews from Engine 12 and Engine 13 were able to locate the children and carry them out of the home. They were rushed to UPMC Hamot Trauma center by ambulance, with CPR underway, but two of the children a 5-year-old boy and his 3-year-old sister did not survive.

According to Erie County Coroner Lyell Cook, the siblings were pronounced dead at the hospital. Cook said an official cause of death will be determined following toxicology tests, but initial indications are that they died from smoke inhalation.

The third child rushed to the hospital is a 5-month-old baby girl. After treatment in the trauma center, she was expected to be flown to a Pittsburgh hospital for further care.

Witnesses said the children’s mother returned home after the fire broke out. Police and fire officials have not said whether any other adults were inside the apartment when the fire started.

Deputy Erie Fire Chief Jeff Carroll said it appears the fire started in the kitchen area of the apartment, but investigators have not confirmed the cause or origin of the fire yet.

Their investigation, along with the assistance of Erie police detectives is ongoing. Erie Police Chief Rick Lorah told Erie News Now that authorities may have more to say on Monday as the investigation progresses.