Salt Lake County sheriff's deputies are on the lookout for a man who robbed the Jordan Credit Union in Riverton late Wednesday, claiming he had a bomb.

Sheriff's Lt. Don Hutson said the suspect -- described as 5-foot-10, medium build, wearing a ski mask and hoodie -- walked into the credit union about 4:50 p.m. and placed a square box on the teller's counter. The man, who also displayed a large black handgun, claimed the box was an explosive device, implying he would set it off if not given money.

A teller filled a cash bag with currency, handed it to the man, and he then fled on foot, leaving the box on the counter. No getaway vehicle was seen in the area, Hutson said.

Deputies responding to the scene X-rayed the box, determining it was empty.