MANCHESTER, N.H. — Firefighters say two workers have suffered serious burns in an underground gasoline storage tank explosion at a Mobil station.

The underground gasoline tank is 8 feet deep and 2024 feet wide. Normally the tank can hold up to 10,000 gallons of gasoline but it was empty on Monday. It was something else that exploded in there just after 1:00 Monday afternoon.

“It would be a flash fire similar to a gasoline fire,” one fire official said.

The pair was relining the empty tank with fiberglass and other chemicals when the explosion occurred. A man working across the street saw smoke coming out of the hole.

“I saw one of the guys climb up out of the hole and kind of roll over on to his back with his hands up so I ran over and I looked down and he was burned pretty bad from the waist down,” said John Brewer, who helped rescue the victims.

Another man was still trapped below. It took several people to get him.

“We pulled him up out of the hole and he was just burned head to toe real bad,” said Brewer.

Both men were MedFlighted to Boston hospitals.

“We're going to make an entry into the tank and document whatever evidence we can find. There was a report that there was a light that had been dropped and broken inside of the tank,” said Chief James Burkush, Manchester Fire Department.

The shattering light may have sparked the flash fire of chemicals being used to line the tank.

Both men are from South Carolina ages 24 and 33. They travel with and work for Tank Tech which is based out of Missouri.

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