The rig caught fire on Tuesday night hours after the gas well was found spewing out of control, prompting the evacuation of 44 workers, according to the U.S. Bureau of Safety and Environmental Enforcement (BSEE).

　　The fire, which burned through the night, caused the beams supporting the derrick and rig floor to fold and collapse over the rig structure on Wednesday morning, the BSEE said in a press release.

　　No one was on board at the time of the fire and nobody was injured, the BSEE said. The source of the ignition remained unknown.

　　The agency added that no sheens were observed on the water surface near the well during flyovers on Wednesday morning, indicating that the gas is burning off with no sign of oil or other hydrocarbons being released into the water.

　　Two firefighting vessels in the area responded to the fire and have now been relocated to a safe distance. A third vessel is en route. One Coast Guard vessel is on site, assessing the situation, and a second one is expected to arrive on Wednesday afternoon.

　　The Coast Guard has reportedly kept nautical traffic out of an area within 500 meters of the site throughout the day. The Federal Aviation Administration also restricted aircraft up to 600 meters above the area.

　　The blowout occurred on Tuesday morning at a shallow-water well about 88 km offshore in 47 meters of water, as the crew were completing work on a sidetrack well to prepare that well for new production.

　　The rig is owned by Houston-based Hercules Offshore and operated by Walter Oil & Gas Corp. The two companies are reportedly working together with the federal authorities to curb the uncontrolled gas flow. The BSEE said that Walter Oil & Gas has begun preparations to move a jack-up rig on location to potentially drill a relief well.

　　It remains unclear what caused the gas blowout. Authorities said that there is no oil spill, and that the magnitude of this accident cannot parallel the 2010 Deepwater Horizon oil spill.

　　In 2010, BP's Deepwater Horizon oil rig exploded off the Louisiana coast, leading to a blowout that lasted for almost three months and spewed millions of gallons of oil into the Gulf. It was the worst accidental marine oil spill in the history of the petroleum industry.