The Bureau of Safety and Environmental Enforcement (BSEE) and the U.S. Coast Guard (USCG) are responding to a loss of well control event that occurred at 8:30 a.m. CST Thursday at Vermilion Block 356 in the Gulf of Mexico (GOM), about 108 miles southwest of Lafayette, LA.

No explosion, fire or oil spill were reported at the site where Rowan Companies plc’s jack-up rig Rowan Louisiana was drilling a well for operator EnVen Energy Ventures LLC of Metairie, LA.

EnVen reported that the well began to flow natural gas during drilling operations. The flow was diverted overboard and work began to shut-in the well. No visible sheen has been reported according to BSEE.

“The rig was jacked-up over the A-Platform, which was producing oil and gas. All production was shut-in and remains shut-in. As a precaution, personnel onboard the platform were evacuated. No injuries have been reported,” BSEE said.

“All personnel currently aboard the rig are safe and non-essential personnel have been evacuated; all well control equipment is functioning as designed,” Rowan said. “There has been no environmental impact, and work is under way to secure the well. The well is located approximately 120 miles offshore Louisiana in approximately 262 feet of water.”

About 20 personnel remained on board to assist in well-control operations, an EnVen spokesman said Friday.

The rig was working on top of a platform that was being fed by six producing wells. These wells were immediately shut in following the incident, EnVen COO Jonathan Garrett told Bloomberg.

“It’s blowing gas and formation water,” Garrett said, as reported by the news service. “We are circulating seawater to try to get it under control. We’re very concerned about a fire and taking all the precautions we can to keep that from happening.”

USCG launched an HU-25 Falcon crew to assess the situation. BSEE is leading a response and will investigate the incident.