Mound Valley, Kan. ? A man was killed Friday after a construction crew ruptured a natural gas line, leading to an explosion in rural southeast Kansas, authorities said.

Labette County Emergency Management Director Jim Cook said Double J Pipeline Construction of Baldwin was replacing old pipe when workers struck the high-pressure gas line.

About 50 people, including construction workers and residents, were evacuated from a one-mile radius of the explosion and fire, officials said. Southern Star Natural Gas Co. was able to shut off gas to the area around noon and firefighters contained the blaze by 1 p.m.

The dead man is believed to be a Double J employee, described by Parsons Fire Chief Tim Hay as an elderly man possibly from Texas or Oklahoma.

Labette County Sheriff William Blunder said he won’t release the man’s name until the remains have been positively identified.

Double J was working on behalf of Admiral Bay Resources Inc. of Centennial, Colo., a gas production company with several wells in the Mound Valley area.

Robert Carington, chief financial officer for Admiral Bay, declined to comment on the incident. Neither Admiral Bay nor Double J were working for Southern Star.

The company’s Web site says Admiral Bay bought a tap into Southern Star’s line near Mound Valley and that the tap was supposed to be open by June.

Southern Star spokeswoman Gayle Hobbs said the accident disrupted gas service to 275 customers near Mound Valley and Liberty. She said the company was working with Atmos Energy to restore service.

The accident is being investigated by the Kansas Fire Marshal’s Office, the Occupational Health and Safety Administration, the Department of Transportation’s Office of Pipeline Safety and the Kansas Corporation Commission, which regulates utilities.

Hobbs said Southern Star will pursue its own investigation.