However a spokesman for the Bureau of Alcohol, Tobacco and Explosives has confirmed the incident is being treated as a potential act of domestic terrorism. They called in Tulsa's bomb squad to help clear the scene and make sure there were no other devices in the area.
The suspected blast mangled the entrance around 10:30 p.m. and scattered debris on a sidewalk outside the military recruitment center in the southeast Tulsa suburb of Bixby, photos show.
Of course, outside of attacks on recruiting offices, there is a history of domestic terrorism in the state of Oklahoma.
Authorities are investigating into what may have caused an explosion next to a Bixby, Oklahoma, U.S. Air Force recruiting office.
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The explosion had damaged the door of the building. The center was closed at the time and no one was injured. But terrorism has not been ruled out as a possible motive.
Rice says the final determination on whether to label the act as terrorism rests with the FBI and that it is now a criminal investigation into the use of an explosive device.
A business owner whose store is close to an Oklahoma Air Force recruiting station that was damaged in a late-night explosion says he suspects it was an attack fueled by anger. The FBI has not yet determined if the two criminal incidents at the respective recruiting centers are linked.