A fired employee of a natural gas distribution company has been indicted on charges he sabotaged the utility's pipelines by puncturing them and tampering with valves, authorities said.

A federal indictment released Friday charges Thomas Lee Young, 58, with 16 counts of destruction of energy facilities between November 2000 and December 2002, and two counts of mailing threatening communications.

Young was arrested Thursday by the FBI and was being held until a detention hearing Tuesday, officials said.

Young is accused of sabotaging Southwest Gas Corp. (search) facilities in Pima and Pinal counties in southeavit, letters sent to Southwest Gas and state regulators and left in some of the sabotage locations demanded two months' wages and reinstatement of retirement benefits for all employees fired since 1994.

Southwest Gas spokeswoman Libby Howell said Young worked for the company from 1979 to 1998 and was a crew leader in its construction department when he was fired. She declined to say why he was terminated.

An affidavit filed by the FBI in federal court in 2004 indicated Young was fired after being arrested on a DUI charge (search) in a company vehicle.

The affidavit said he lost 60 percent of his retirement benefits.

Young's attorney, Alfred "Skip" Donau, said he did not believe Young was convicted of DUI and that his client had no criminal record.