DENVER (Reuters) - A blaze engulfed a Colorado oil tank battery on Thursday, killing one worker and injuring three, authorities said.

Emergency crews were dispatched to the Anadarko Petroleum Corp plant outside the town of Mead and found the site in flames, the Weld County Sheriff’s Office said in a statement.

Two workers were taken to a local hospital for burns while a third worker was taken to a separate hospital for undisclosed injuries, the sheriff said.

Firefighters, sheriff’s deputies and Anadarko crews combed through the site and found a fourth worker who was “declared dead at the scene,” police said.

None of the workers has been identified and the cause of the fire is under investigation, authorities said.

Anadarko spokeswoman Helen Wells said the workers were with a contract crew performing maintenance at the site when the blaze started.

Thursday’s fire marked the third fatality in little over a month connected to oil and gas facilities operated by Texas-based Anadarko in the same area, about 35 miles north of Denver.

In mid-April, an explosion at a home in Firestone, about five miles away from Mead, was traced to a cut and uncapped natural gas line leading away from a dormant well owned by Anadarko.

State investigators said the gas had seeped for months into the home and somehow ignited, killing two men inside and severely burning a woman.

That explosion prompted Colorado Governor John Hickenlooper to order all oil and gas companies operating in the state to locate, inspect and cap all similar “flowlines” within 1,000 feet (305 meters) of any occupied buildings.