A natural gas well exploded and caught fire Saturday afternoon, killing at least six of the 13 workers on the crew. Five others were taken to hospitals.
"Two appear to be OK," said Bob Lane, chief operating officer for Sonat Exploration Co., which owns the well.
The conditions of those hospitalized were not immediately available.
The intense heat from the fire prevented rescue crews from getting close enough to remove some of the bodies of those who were killed.
"The derrick is leaning and we're afraid it will fall over. We're also afraid some of the pipes (used in drilling) will blow," state police Lt. Mike Edmonson said.
The crew was completing a new well in Bienville Parish, about 45 miles east of Shreveport, when it blew about 2 p.m., Lane said.
Edmonson said the fire was expected to burn through the night. The cause of the blaze was not immediately known.
Lane said the company's top priority "is to take care of the people. No. 2 is to get the well under control. Then and only then will we investigate to find out what happened."
The well, in a large clearing in north Louisiana's piney woods, shot flames 100 feet or more into the air with a roar like a jet engine, state police spokesman Chris Johnson said.
The framework of the well was starting to melt in the intense heat, leaning toward a small patch of woods. Police pulled back in case it fell and set the trees on fire, though it appeared unlikely that the blaze would spread to the woods, authorities said.
Black smoke rose hundreds of feet above the well, said Tammy Collinsworth, owner of Bryceland Mall a few miles away. Roads to the well were closed off, she said.
Firefighters were pouring water onto drums of methanol, which is used for drilling, to try to keep those from exploding. Well control teams from Texas were headed to the site.