BIXBY, Oklahoma - The FBI has been called in to investigate an explosion at an Air Force Recruiting office in Bixby late Monday. Authorities initially said it was believed to be an act of domestic terrorism, but a federal agent later said it is being investigated as a criminal act.

They don't know if the bombing was politically motivated or if it may have been an act by a disgruntled ex-employee.

The explosion heavily damaged the front doors of the recruiting station in the Post Rock Plaza in the 10400 block of South 82nd East Avenue just off South Memorial Drive.

Bixby and Tulsa Police received several reports of the explosion just after 10:30 p.m. Bixby requested Tulsa Police bomb squad because of a possible pipe bomb.  TPD along with the ATF and FBI also responded.

The plaza's property management tells News On 6, nearby Genghis Grill has surveillance video of the incident. They hope to view it sometime Tuesday morning, but the FBI will look at it first.

Police said the recruiting station was closed at the time, and no injuries were reported. 

A music store just down from the recruiting store opened Monday, July 10. The owner said his business wasn't damaged.

There were cleaning crew members in the Nature Conservancy store next door. They heard the explosion and immediately ran out of the strip mall, News On 6 was told.

A mirror was knocked from the wall at that store.