Federal authorities have confirmed an explosive device was set off outside an Air Force recruiting center near Tulsa, Oklahoma.

Bixby police say the blast was reported around 10:30 p.m. Monday. Bixby is about 15 miles (24.1 kilometers) south of Tulsa.

FBI Agent Jessi Rice says the recruiting office was closed at the time of the explosion and no one was injured. The extent of the damage is not yet known.

Investigators with the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives are at the scene. Rice says the Tulsa police bomb squad was the first to respond.

No arrests have been made. ATF Special Agent Meredith Davis says the blast is being investigated as a possible act of domestic terrorism.