A man was violently attacked as he tried to stop a gang of armed robbers who were fleeing from a raid on a post office in Greater Manchester.
Four masked men, armed with crowbars and hammers threatened and attacked staff at the shop on Pole Lane in Bury, at about 1400 BST on Thursday.
As they were fleeing with cash, a customer took a spade from his van parked outside and challenged the men.
The 47-year-old suffered head injuries and was taken to hospital.
The post master also suffered an injury to his head, police said.
The gang escaped in a stolen black Seat Altea which later was found abandoned in Hollins Lane.
Police believe one of the robbers suffered injuries to his arm.
Det Insp Jane Little, of Greater Manchester Police, said: "This would seem to have been a well planned raid but nothing would have prepared these dangerous robbers for the actions of the man who acted extremely bravely and without a second thought for his own safety.
"As a result he suffered a very serious injury and I am appealing to the public to help me identify the offenders.
"While the man's actions should be commended we would never encourage anyone to intervene in such a way."
The Post Office is offering a reward for information leading to the arrest and conviction of those responsible.