ERIE (AP) — An early morning fire at a residential building housing a day care center killed five children and sent the owner to the hospital, authorities said.

The fire was reported at about 1:15 a.m. Sunday, Chief Guy Santone of the Erie Fire Department said.

The victims ranged in ages from 8 months to 7 years, Santone said. The Erie Regional Chamber and Growth Partnership lists a day care at the fire address.

Valerie Lockett-Slupski, standing across the street from the fire-damaged house, said she was the grandmother of four of the children, and that they were staying at the day care because their parents were working overnight, the Erie Times-News reported. She said the family had two boys and two girls and had used the day care for almost a year.

“So we are all at a loss, trying to figure out how this happened,” Lockett-Slupski told the newspaper.

The owner of the day care was flown to UPMC Mercy for treatment, Santone said. He said a neighbor was also injured.

Chief Fire Inspector John Widomski told the newspaper that the fire appeared to have started in the living room area on the first floor. The department’s two fire inspectors and three Erie police detectives trained in fire investigations are working to determine the cause of the blaze.

The chamber site lists the Harris Family Daycare at that address as “a 24 hour, 7 days a week childcare service including holidays. We provide transportation and teach kids age appropriate skills.” The state Department of Human Services Office of Child Development and Early Learning listed the day care as in compliance with requirements following a Dec. 28, 2018, inspection.