NEW YORK (Reuters) - A worker has died due to injuries from a fire at HollyFrontier’s El Dorado, Kansas refinery, a local hospital confirmed on Tuesday.

A fire was reported at the 150,000 barrel-per-day refinery on Monday and a worker in the immediate area was hurt, the company confirmed via email on Monday.

The worker died overnight, according to Via Christi Hospital St. Francis without providing any additional details.

“We are deeply saddened by the loss of our friend and colleague. Our thoughts and prayers are with his family and friends,” said George Damiris, CEO and president of HollyFrontier Cos, in a statement.

The worker was a member of the local chapter of the United Steelworkers, according to the labor union.

“It is a difficult time for all. Our union is working with OSHA to investigate this incident and find the root cause(s) so it does not happen again.” Lynne Hancock, spokesperson for the USW’s oil sector, said via email.

The fire started after a furnace associated with the plant’s reformer unit blew, a source familiar with the plant’s operations told Reuters on Monday.

The 22,000 bpd reformer unit was shut down, but the rest of the refinery remains in operations, the source said.