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Fire department: A sudden rush of air creates a "fireball," engulfing the firefighters

Two firefighters suffering from burns are in critical condition Saturday, officials say

The cause of the fire is under investigation

CNN —  

Seven firefighters were hospitalized after a house fire in Riverdale, Maryland, authorities said.

The fire broke out at a one-story, vacant house shortly after 9 p.m. Friday, the Prince George’s County Fire Department said Saturday.

“Preliminary reports indicate that firefighters had initiated an interior attack on the fire when a sudden rush of air, fanned by high winds, entered from the rear of the house either from a door or window being opened or broken out,” the fire department said in a statement. “The sudden addition of a large amount of fresh air into the fire environment created a ‘fireball’ inside, engulfing the firefighters.”

The injuries included burns, fractures and lacerations, fire officials said.

By Saturday morning, four of the firefighters had been released; two remained hospitalized in critical condition with burns, and one was in good condition with injured ribs, fire department spokesman Mark Brady said.

The cause of the fire is under investigation.

CNN’s Greg Seaby and Joe Sutton contributed to this report.