An early morning fire in Pennsylvania at a residential building housing a daycare centre killed five children and sent the owner to the hospital, authorities said.

The fire was reported in Erie, a northwest lake town, at about 1.15am on 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 daycare 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 daycare 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 daycare 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 daycare was flown to hospital for treatment, Santone said. He said a neighbour was also injured.

The 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 were 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 daycare as in compliance with requirements following a 28 Dec inspection.