A man robbed a Family Dollar store in Tucker at gunpoint Monday morning, DeKalb County police said.

A witness told police she was waiting in line at the Brockett Square location to buy something when she saw the suspect pull out a black gun, point it at the cashier and demand the store's cash at about 11:15 a.m., the police report said.

The cashier backed up and said she couldn't open the register, so the witness told the suspect to calm down and she would open it for him. She opened the register, placed the till on the counter and the suspect emptied it, taking $100. He fled the store toward Brockett Road.

The suspect was described as a black male about 5 feet 10 inches, 150-165 pounds with a slim build. He wore a red Atlanta Falcons hat, a red and gray Falcons jacket, black jeans and brown boots.