An explosion at a newly drilled oil well in western North Dakota killed two workers and severely injured two others, officials said.
The fatal fire was one of two oil field-related blazes reported in the Williston area Wednesday. The other was much smaller and no one was hurt. Both happened in a part of the state that is experiencing what many are calling the largest oil boom in recent North American history.
The rig explosion happened around 5:40 p.m. McKenzie County Sheriff Ron Rankin said 21-year-old Brendan Wegner of Montello, Wis., died at the scene. Ray Hardy, of Mohall, died Thursday morning at a hospital in St. Paul, Minn., according to the hospital.
Two other men _ Doug Hysjulien of Williston and Michael Twinn of Tioga _ were hospitalized in critical condition in the burn unit at Regions Hospital in St. Paul.
"One of the workers at the scene said they were severely burned," Rankin said.
Authorities have not yet determined the cause of the explosion, Rankin said.
Rankin said the men were working at a workover rig owned by Carlson Well Services Inc. A man who answered the telephone Thursday at the Powers Lake-based business said the company had no comment and hung up.
Alison Ritter, a spokeswoman for the state Department of Mineral Resources, said no oil or hazardous material escaped from the well.
"The fire is out and there was really no well control issue," she said Thursday.
Houston-based Oasis Petroleum Inc. owns the well, which had been producing for about a month, said Taylor Reid, the company's chief operating officer. None of the company's employees was at the well site when the explosion happened, he said.
The other fire in the area was small. Williams County Sheriff Scott Busching said a pumping unit on a tank that separates saltwater from crude oil caught fire and was quickly extinguished.
"There was no explosion, nobody was hurt, and nobody was even there," Busching said.
The recent fatalities bring to three the number of oil patch related deaths since July 1, said Bryan Klipfel, director of the North Dakota Workforce Safety and Insurance agency.
North Dakota recorded five oil field-related deaths in fiscal 2011, up from three in fiscal 2010, Klipfel said.
The number of injuries in the state's booming oil patch jumped from 747 in fiscal 2010 to 1,897 in fiscal 2011, a more than 150 percent increase, he said.