Johannesburg - The theft of a cashbox from a security guard at a mall in Rosettenville, south of Johannesburg, which resulted in the death of a metro police officer, may have been an inside job.The mall's CCTV footage video which is being circulated on Facebook, shows a security guard walking out of a Pick n Pay store with the cash box in hand. A man on a crutch follows the guard out of the store and approaches him from behind causing the security guard to stop a few meters away from the store.A second man also approaches the security guard, who is now cornered in front of a pillar. The second man, who is holding a bag, takes out what looks like a bottle and pours its contents over the cash box while the security guard stands calmly, seemingly allowing him.The metro police officer, walking towards the store, observes what is happening and attempts to draw his gun.He is quickly attacked by the man using the crutch. After a bit of wrestling between the two men, the officer is seen falling to the ground and lying still. People in the area are seen running in different directions.The two robbers then flee the scene, down the escalators and the security guard calmly walks away from the scene in a different direction, leaving the officer lying there.The incident took place on Monday.At the time, Johannesburg Metro police spokesperson Chief Superintendent Wayne Minnaar said the 60-year-old officer was on his way to withdraw cash at an ATM just before 15:00 near the store when he came across the robbery.Minnaar said the officer was shot once and fell on the floor, then he was shot two more times in the upper body.The robbers fled the scene with the cashbox, but the anti-theft dye was activated shortly afterwards making the cash unusable, he said.