A fire has broken out on a blown-out gas well in the Gulf of Mexico.
Natural gas has been spewing out of control from the well after the blowout forced the evacuation of 44 workers on a drilling rig about 55 miles off the Louisiana coast, authorities said.
Eileen Angelico of the Bureau of Safety and Environmental Enforcement (BSEE) confirmed that the evacuated rig had caught fire, but there were no reports of injuries.
Ms Angelico said it was not clear what caused the gas to ignite, and it was not known what efforts to extinguish the blaze were being made.
Personnel from Wild Well Control are at the site to develop a plan to shut down the flow of gas, said Jim Noe, executive vice president of Hercules Offshore, owner of the drilling rig where the blowout occurred.
Mr Noe stressed that gas, not oil, was flowing from the well. He said it is an important distinction because gas wells in relatively shallow areas - this one was in 154ft of water - sometimes tend to clog with sand, effectively snuffing themselves out. "That is a distinct possibility at this point," he said. "But until we have our Wild Well Control personnel on the rig, we won't know much more."
The Coast Guard and the BSEE kept state and coastal officials apprised of the well's status.
"According to federal officials, there is no imminent danger at this time," said Kevin Davis, head of the Louisiana governor's homeland security office said.
Still, the Coast Guard kept nautical traffic out of an area within 500 metres of the site, and the Federal Aviation Administration restricted aircraft up to 2,000ft above the area.
The BSEE said inspectors flying over the site soon after the blowout saw a light sheen covering the area, but it was dissipating quickly.
Earlier this month, a gas well flowed for several days before being sealed off the Louisiana coast.
In 2010, an oil rig exploded off the state's coast, leading to a blowout that spewed millions of gallons of oil into the Gulf in the worst offshore disaster in the United States.
Coastal officials stressed that Tuesday's blowout was nothing of that magnitude.
Tuesday's blowout occurred near an unmanned offshore gas platform that was not producing natural gas, said Ms Angelico. The workers were aboard a portable drilling rig known as a jackup rig, owned by Hercules, which was a contractor for exploration and production company Walter Oil & Gas.
Walter Oil & Gas reported to the BSEE that the rig was completing a "sidetrack well" - a means of re-entering the original well bore, Ms Angelico said.