Police have warned that three masked men who viciously attacked a postmaster could strike again.

They forced their way into a Helmsley post office, North Yorkshire, with a chainsaw, on Tuesday.

Postmaster Geoff Simpson was taken to the Friarage Hospital, Northallerton, after the attack and is being treated for injuries to his nose, ribs, eyes and shin.

From his hospital bed, Mr Simpson said: "I locked the back door when I heard a loud bang, and then a chainsaw started cutting through the door."

The men pushed in, spraying Mr Simpson in the face, then punched him to the ground and kicked him.

They demanded to know where the safe keys were, and although they did not gain access to the safe, they left with an unknown quantity of cash.

A vehicle was seen leaving the rear of the building, and was believed to have travelled along Pottergate and then Bondgate.

Detective Sergeant Ian Fieldsend described the attack as particularly vicious. He said police were alerting all post offices to be extra vigilant in case of a further attack, and increasing patrols to reassure the public.

Officers would like to hear from a white man with a moustache seen at the back of the post office on Tuesday lunchtime, in order to eliminate him from the investigations.

They also want to talk to the three men seen in a dirty red Ford Mondeo near Helmsley that morning.

Anyone with information is urged to call the witness line on (01723) 509662.