People angered by the number of armed robberies at their local post office in Greater Manchester tried to block in a getaway driver during the latest raid.
Two masked men, armed with crowbars, burst into the post office in Windmill Lane, Denton, just before 1000 BST.
When people saw what was happening, four nearby builders blocked in the car of a third man waiting outside.
The driver drove on to the pavement to flee, picking up the other two - who stole a large amount of cash - later.
One of the builders smashed the window of the car - a blue Honda Civic - in a bid to prevent his escape.
Police said the two others, who fled on foot, attempted to steal another car, but when the owner threw the key at them it broke and they were unable to start it.
The getaway driver picked the pair up further down the road and the car was later found abandoned in nearby Ash Road.
Det Con Michelle Lomas said: "Clearly, people in this area have had enough of their vital services being targeted by criminals after this post office was robbed in the past.
"While we wouldn't recommend anyone else tackling an armed robber, we must recognise that this was incredibly brave and a real show that crime and its perpetrators are not welcome in this community.
"We are now doing everything in our power to find those responsible and ensure they face justice."
Extra patrols have been carried out in the area after previous robberies and detectives are working with shop management to help improve security.
One member of staff was treated by paramedics after being punched in the face during the raid.