The botched robbery happened around 8:30 p.m. when the suspect, wearing a hooded sweatshirt and a face mask, entered the convenience store and approached the counter to buy cigarettes, according to the West Covina Police Department.
Surveillance video shows the cashier place the item in a plastic bag when the suspect lifts his sweatshirt and appears to brandish a gun in his waistband. The cashier then starts filling up the bag with money from the register.
Just as the employee finishes putting all the cash in the bag, the police sergeant happens to enter and even walks right next to the robber.
The employee alerts the sergeant just before the suspect runs out the door. Footage shows the sergeant immediately chase after the suspect.
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The suspect was later apprehended. Police identified him as Ramon Gonzalez, 48, of La Puente.
A loaded handgun and about $400, which was returned to the cashier, was recovered from Gonzalez, police said.
Gonzalez was booked on suspicion of robbery, felon in possession of a firearm and carrying a concealed weapon.
It's the second time in the last few days that a local law enforcement officer walked into a convenience store and foiled a robbery. A Los Angeles County sheriff's deputy walked in on an armed robbery in progress at a 7-Eleven in Carson on Saturday. Four would-be robbers were taken into custody without incident when the deputy was able to stop them and call for backup.