Los Angeles County Sheriff's Department Deputy Luis Cisneros walked into a 7-Eleven that was getting robbed Tuesday.

Just moments before Cisneros walked into the store, a group of robbery suspects stormed the counter and demanded the clerk open the register. Security camera footage showed one of the suspects pointing the gun at the clerk's head. Seconds after, Cisneros, a 9-year veteran of the department, unsuspectingly walks into the store to simply check on the store clerks he spoke to earlier that day. 

He immediately pulled out his firearm right as the suspects tried to escape. 

"When that happened I realized that there might have been someone outside that tend to lookouts or getaway drivers," Cisneros told CBS. 

Cisneros radioed for help as he constantly checked his back for anyone trying to ambush him.

All four suspects were arrested by Cisneros and his backup.