Detectives in Sussex have re-opened a 35-year-old murder inquiry after workmen found evidence from the case locked in a basement.

Contractors upgrading a sprinkler system at Brighton Police Station uncovered a room which contained several boxes of items relating to the death of Keith Lyon.

The knife used to kill the 12-year-old schoolboy was one of the items found.

Police hope the dicovery, along with developments in forensic technology, will help them track down the killer.

The murderer could be dead but if we have his DNA, we can find out who did it

Detective Inspector Bill Warner

Keith Lyon's body was found on 6 May 1967, on a bridle path in an area between Ovingdean and Woodingdean, East Sussex, known as Happy Valley.

The murder weapon was found days later in school grounds a mile away.

The knife was still stained with Keith's blood, along with that of another unknown person.

The discovery, made on Tuesday, has raised hopes that forensic tests which were not available at the time of the murder will shed new light on the inquiry.

'Knife mislaid'

Detective Inspector Bill Warner, of Brighton and Hove City CID, said that at some unknown time the evidence was stored in the room.

He said: "The most disturbing fact was we mislaid the exhibits.

"The case was reviewed several years after the initial inquiry and again in the mid-70s.

"It was always thought that the knife had been mislaid somewhere.

"The significance of the find is that we have got the evidence now and secondly, we have got the chance of forensic retrieval to identify the offender.

"There are a whole host of what ifs. He (the murderer) could be dead but provided we have his DNA, we can find out who did it."

Detectives will look at the original suspects in the case, one of whom has since died, to see if they can get a DNA match.