NYACK, N.Y. — A presumed natural-gas explosion in a college building Tuesday blew out windows, sent a door sailing through the air, and injured seven people, but authorities said none of the injuries was life-threatening.
After the blast, gas rose to ‘‘explosive’’ levels — as high as 70 percent — in the manholes at Nyack College outside New York City, said Mike Donohue of Orange & Rockland Utilities. He said natural gas was assumed to be the cause of the explosion, which happened shortly before noon and caused serious damage to the basement and first floor.
A female student and six employees were taken to the hospital. The school sent out a tweet saying that ‘‘Everyone is doing ok.’’
The explosion also started a fire that was put out by sprinklers, said Gordon Wren, director of Rockland County Emergency Services.
Donohue said the gas was turned off and the detected levels of it subsequently fell. Utility workers were trying to find the source of the leak.