JEANERETTE, La. (AP) _ A tugboat pushing two barges hit an offshore natural gas pipeline Thursday, causing an explosion that killed three people, left three missing and sent flames shooting 100 feet high, the Coast Guard said.

The tug and barges hit the gas line at about 12:30 p.m. in West Cote Blanche Bay, about two miles from shore and about 100 miles southwest of New Orleans, said Petty Officer 2nd Class Nyx Cangemi.

The tug boat had two people on it, and six people were on the barge, Cangemi said. Coast Guard rescue crews recovered three bodies and two survivors. Three people remained missing.

One survivor was severely burned and taken to a hospital, said a Coast Guard spokeswoman, Veronica Bandrowsky, said. The other person was not injured, she said.

Three people remained missing late Thursday. A helicopter crew was to remain out until midnight and return at first light Friday, Bandrowsky said, and water patrol of a local parish were to be out through the night.

The first report of the explosion came from a man on a nearby beach, Cangemi said.

``There were 100-foot flames at that point,'' he said.

The fire was out by 3 p.m., Cangemi said.

Gulfport Energy Corp. said the accident involved two contracted vessels doing work for the company in a large energy field. The company said that all its employees were accounted for but that it was still trying to get information on its contract workers.

``We are deeply concerned for all those involved,'' Gulfport CEO Jim Palm said in a statement.

The cause of the accident remained under investigation.