TULSA, Okla. (CN) – Federal officials said Tuesday afternoon that they are no longer investigating a pipe bomb explosion that damaged a northeast Oklahoma Air Force recruiting station as a possible act of domestic terrorism, adding that the blast could be the work of a disgruntled employee or a prank.
FBI agent Jessi Rice said the explosion in the Tulsa suburb of Bixby is not being called domestic terrorism because investigators have not determined a motive and have not identified a suspect.
Rice said the blast currently is a criminal investigation into the use of an explosive device.
"We don't know if it was a disgruntled employee, an act of terrorism or someone playing games," Rice said at a news conference.
A device was detonated at 10:30 p.m. at a shopping center in Bixby, damaging glass windows and blasting a front door off of its hinges and into the parking lot. Federal Bureau of Investigation agents spent up to six hours collecting evidence at the scene, the Tulsa World newspaper reported.
Witnesses said a person on a red motorcycle threw a backpack at the office that exploded, NBC-affiliate KJRH-TV reported.
FBI spokeswoman Jessi Rice said the agency will try to re-create the pipe bomb to find out how it was made and by whom. She said they do not have a motive or suspect.
The FBI and Bureau of Alcohol, Tobacco, Firearms and Explosives are leading the investigation, while Bixby and Tulsa police were the first responders to the explosion.
Rice said the bombing is “suspicious” given earlier reports of vandalism at another recruiting office nearby.
“There is no known connection,” she said. “But it is quite ironic that that happened.”
Rice said the federal criminal charges that will be filed depend on where the investigation goes, that weapons of mass destruction charges are possible.
Bixby police spokeswoman Many Vavrinak said the explosion was located near an “affluent suburban community” where this kind of event is not common.
“We do not have a lot of incidents where the FBI has to come investigate,” she said.
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