Sept. 6 (UPI) -- An explosion at an East Chicago, Ind., post office occurred Wednesday night, injuring at least one person, officials said.
Fire officials said the explosion might have come from a package and at least two pipe bombs were found on the scene, reported NWI.
"Right now the FBI, ATF, all the agencies are here, we're investigating," said East Chicago Fire Department Chief Francisco Mendez, according to NBC Chicago. "I can confirm there was at least one detonation."
Two employees were in the building at the time of the explosion. On woman was injured but her condition has not yet been reported by officials.
NWI reporter Lauren Cross tweeted that a bomb disposal robot was brought onto the scene.
The post office is located about 24 miles outside of downtown Chicago.