At least two workers died on Tuesday as a self-elevating oil maintenance platform tilted off Mexico's east coast, forcing the evacuation of 101 employees, the Pemex energy firm said.
The jackup rig, owned by a Pemex contractor named Typhoon, "is continuing to tilt" in the Sound of Campeche area of the Gulf of Mexico, the company said on Twitter at around midday.
"We regrettably confirm the death of a second worker in the accident at the Troll Solution platform," Pemex said, without giving details about how the two workers died.
The platform was positioning itself to conduct maintenance work for the wells of another rig when it began to lean. A jackup rig has movable legs that can raise its hull over the sea.
In another incident in the same area last month, a Pemex rig caught fire on the Sound of Campeche, killing four workers and leaving three missing.
A Pemex spokesman was unable to give details about Typhoon.
Typhoon appears to have a website that lists a Mexico City address and telephone number, but a woman answering the phone said nobody was available for comment.
The website says Troll Solution flies the flag of the Pacific island nation of Vanuatu and was built in 2010. It has three movable legs, a crane and a helipad.
The company was incorporated in 2013 to "satisfy demand in the Gulf of Mexico for heavy well intervention and workovers" as well as maintenance of platforms, the website says.