STILWELL, Oklahoma - What are believed to be three pipe bombs exploded at a business in Stilwell early Monday morning.

The FBI says there were two explosions at Anderson Gas and Propane on state Highway 59 between 3 and 4 a.m. 

When an officer arrived on scene, there was a third explosion sending shrapnel into the officer's patrol car.

Stilwell Police say no one was injured.

The FBI believes these explosions were intentional and not an accident.  The explosions caused only minor property damage.  

The FBI, ATF, Stilwell Police, Oklahoma Highway Patrol, and Adair County Sheriff's Office are investigating.  

Anyone with information regarding these explosions is urged to immediately contact the Oklahoma City Division of the FBI at 405-290-7770.  You may remain anonymous.