Two masked men carrying a shotgun and a long rifle robbed a Walmart in Atascocita.
Harris County sheriff's deputies said around 11 p.m. Tuesday, the men stormed into the store on FM 1960 at Atascocita Road and demanded cash from the employees.
Investigators said the robbery happened at the exact same time thousands of dollars in cash was being moved from the cash registers to the vaults.
"They immediately walked over to the money box area that the employees move from cash register to cash register," Deputy Thomas Gilliland said. "They grabbed the cart and immediately exited the door."
Detectives said the men loaded the trays of cash into the trunk of a white Ford Taurus and then took off.
Investigators are reviewing surveillance video to see if it can provide a clue to the robbers' identity.
Employees and customers were inside the store during the robbery. No one was injured.