A MYSTERY letter posted in Dorset may help solve a 13-year-old murder inquiry.

The hand-written letter bears a county postmark and claims to reveal the identity of the killer of a Kent man.

Police in Thanet, Kent, are appealing for the author of the letter to come forward. They've been looking for the murderer of double glazing salesman David Short for over a decade.

Mr Short answered his door on the evening of Thursday, September 22, 1988. He was blinded with an incapacitant spray and hit on the head with an unidentified object.

He died minutes later of his injuries.

The investigation into the brutal murder revealed no motive for the attack and left police in the area stumped.

Now the letter from Dorset claims to reveal the name of the murderer.

Thanet police spokesman Gemma Pettman said: "Officers do think it may provide the key to the inquiry. They do not think it's a crank or some elaborate hoax.

"We don't know what the motive of the letter was, but in these circumstances there's always a lot of speculation about someone wanting to get something off their chest.

"But we don't have any firm idea why someone would want to pass on this information now, after 14 years.

"The ideal outcome of the inquiry would be if the author of the letter came forward. Otherwise maybe someone else knows something about it."

She said police were hoping the fact that an incapacitant spray was used might help in the investigation.

"It's not the sort of thing that people would be able to get their hands on easily 13 years ago," said Ms Pettman.

Investigating officer, Detective Inspector Jon Holl, said: "The author of this letter clearly has information that is key to this inquiry and we would appeal for that person to come forward and contact us as soon as possible.

"We can assure their confidentiality."

Anyone with information on the letter is asked to call Margate Police Station on (01843) 222208.