San Antonio police have requested help from the public as they try to track down a man who they say robbed a Valero in the 4300 block of W. Commerce on Aug. 20.

The store's cashier told police she was standing behind the counter and was helping a customer when the man pictured here walked into the store and tapped the counter with a gun.

The cashier said the man demanded money, so she put cash in a bag for him. After she handed over the bag, the suspect ran out of the store.

Crime Stoppers will pay up to $5,000 for information that leads to an arrest. The number to call is (210) 224-STOP (224-7867). Callers may remain anonymous.