(Reuters) – One person has died and six others have been rescued after a commercial “lift boat” used to service oil rigs capsized in hurricane force winds several miles south of Port Fourchon on the Gulf of Mexico, the U.S. Coast Guard said on Wednesday.

A dozen people were still missing after the 129-foot commercial vessel capsized in rough seas about 4:30 p.m. on Tuesday, officials said.

Two Coast Guard cutters, a military helicopter, airplane and a small fleet of volunteer private vessels were involved in the searched operation, said Coast Guard Captain Will Watson.

“Unfortunately one person was recovered deceased on the surface of the water,” he said, adding that the winds were about 80 miles per hour (129 km per hour) to 90 mph at the time of the accident.

Two people were rescued by the Coast Guard and four others were pulled from the waters by people on other vessels, he said.

“My heart and the collective hearts of our team goes out to the families,” Watson said, adding that they are working to find other survivors.

The high winds, with some hail and flooding are expected to continue in southeastern Louisiana, according to the National Weather Service. There is a threat of severe weather to overnight in the region and a flash flood watch is in effect till Thursday morning.

The vessel is owned by Seacor Marine, a Houston, Texas-based transportation company, according to media reports.

A representative for the company was not immediately available for comment.

(Reporting by Aakriti Bhalla in Bengaluru; Additional reporting and writing by Rich McKay in Atlanta; Editing by William Maclean and Mike Harrison)