MASKED men threatened and punched a security guard when they raided a petrol station.

And it is thought the robbers could be behind another raid in Farnworth two days earlier.

Detectives last night said they could not rule out a link between the two robberies.

Security staff were re-filling a cash machine at Kearsley service station, in Manchester Road, at 6.15am yesterday when they were targeted by two men.

They were threatened by the men, and one security guard was punched in the face, suffering a minor injury.

But the robbers did not get any cash and escaped with only an empty money cassette.

They drove off in a white Volvo, heading towards Swinton.

The men were both described as being 6ft 1in tall and wore dark clothes and balaclavas.

Detective Constable Stuart Round, of Bolton CID, said: “While the men did not manage to steal any cash, this was clearly a well planned robbery.

“I would urge anyone who may have overheard someone planning this raid or has any knowledge of who might be responsible to call police.

“All information will be treated in strict confidence.”

Police were at the petrol station yesterday morning as they launched an inquiry into the attempted robbery.

One line of inquiry is whether the incident was linked to an armed robbery at Costcutter convenience store, in Campbell Street, Farnworth, at 8am on Tuesday.

Security guards re-filling a cash machine inside the shop were threatened with a sledgehammer by two masked men.

The robbers left empty-handed when they were disturbed by the police, but no arrests have yet been made in connection with the incident.

Anyone who has any information about either robbery is asked to call Bolton CID on 0161 856 5740, or charity Crimestoppers, anonymously, on 0800 555 111.