A 28-year-old man facing federal charges in a pipe bomb explosion outside an Air Force recruiting center in Oklahoma had been enlisted in that branch of the military and was decorated for his service, a military official said Wednesday.

Oklahoma Air National Guard Capt. Jennifer Proctor told The Associated Press that the suspect, Benjamin Don Roden, enlisted for Air Force active duty in April 2012 and joined the state's air national guard in October 2014.

Proctor said Roden had been a senior airman whose job involved fire protection, but that he was discharged from the air national guard's Tulsa-based 138th Fighter Wing in April. She did not provide a reason for his discharge.

According to the arrest report Tuesday, Roden faces federal charges of possession of explosive materials and destruction of government property in the blast Monday night in a commercial area in the Tulsa suburb of Bixby. The recruiting center was closed at the time and no one was hurt, although the office door was blown off in the explosion.

Roden received several decorations, including the Global War on Terrorism Expeditionary Medal, Proctor said. The medal is awarded to military members who have deployed overseas in direct service to the war on terror since the Sept. 11 attacks. Roden also received the Air Force Expeditionary Service Ribbon with gold border, with the border signifying that he was in a combat zone, she said.

Roden is expected to make an initial court appearance Wednesday. He hasn't been formally charged and it's unclear whether he has a lawyer. He is jailed without bond.

FBI agent Jessi Rice said federal authorities are no longer investigating the pipe bomb as an act of domestic terrorism, telling reporters that the blast could have been the work of a disgruntled employee or a prank.

Messages left for numbers listed for Roden's mother and sister were not immediately returned Wednesday.

___

Associated Press researcher Rhonda Shafner in New York and writer Tim Talley in Oklahoma City contributed to this report.