Four other individuals were injured in the fire. Two were treated and released at local hospitals following the accident on Friday; the two more severely injured are being treated at the burn center at South Alabama Medical Centre in Mobile.
The fire was under investigation over the weekend by the federal Occupational Safety and Health Administration (OSHA) and Halter's in-house safety and environmental group.
Halter Marine CEO William B. Skinner said on Saturday afternoon, "We are required to report to OSHA all accidents in industry as part of our guidelines. The investigation is ongoing. We haven't determined a cause."
Flash Fire Accident Did Not Damage the Tugboat
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"That will continue, out of respect," Skinner said. "There was no damage to the tug. This was just a flash. We're trying to find out how it happened. The work they were performing was cleaning a tank and getting it ready to paint. During the course of that, the solvent being used something happened to cause a flash. We don't know what that is."
According to the Sun Herald, one of the men involved was an employee of Halter, while the other five worked for subcontractors, including Global Contracting, B&D Contracting and Masse Contracting.
It is not known if the two men who were killed in the flash fire were employees of Halter or of one of the subcontracting firms. The coroner in the case was identified as Vicki Broadus of Jackson County.