The Capon Valley bank, in the Baker region of West Virginia, was raided on May 14 around 11am by disguised robbers, one of whom had a gun.
One suspect was a stocky man wearing a clown mask with orange hair, a large cloth nightgown, blue jeans and brown boots.
The other suspect, who it is thought may be a woman, wore a brown monkey mask, black hooded jumper and grey tracksuit trousers, and is believed to have been in possession of a firearm.
An undisclosed sum of money was taken from the bank as the duo escaped in a blue Chevrolet, which was found on fire minutes after the robbery. The getaway car had been stolen from a dealership in a nearby town and it is believed the pair switched vehicles in the aftermath.
Police are continuing to investigate the case.