EYE-witnesses today described the dramatic moment when a Royal Mail security guard was hit over the head with a metal bar after being attacked by masked raiders outside a Bolton post office.

Four thugs attacked the guard as he walked towards Breightmet post office on Bury Road.

Workers at nearby shops looked on in horror as the raiders knocked him to the ground before escaping with a box full of cash in the lunchtime raid yesterday.

Joan Davies, who works at Allen's Bakery, was serving customers when she saw the guard being hit.

She said: "We looked outside and saw the security guard on the floor.

"One of the men was hitting him over the head with something which looked like a long, metal bar. There were dints in his helmet."

She added: "We then saw them jump in the car and escape with the box."

Another trader, who did not want to be named, said: "I heard a woman shout: 'There's an armed robbery, they've got guns'. I went back into my shop and phoned the police.

"It gets quite scary when you hear there's guns involved. You don't expect it to happen around here."

Traders close to the post office said they had applied for CCTV cameras after problems with crime in the area, but had been unsuccessful.

If their bid had been given the green light the raid may never had happened, they said.

A police spokesman said: "Four men wearing balaclavas and anoraks entered the premises and threatened staff with a handgun before escaping with a substantial amount of money.

"They drove away in a green VW Golf with a new style registration towards the Farnworth area. A male security guard was hit over the head several times with a metal object but his injuries are not serious."

"We would appeal to anyone who witnessed the robbery or saw anything suspicious beforehand to come forward."

Anyone with information is asked to call 0161 856 5752.