A UFO and paranormal investigator has joined the search for the truth about North Yorkshire's mysterious big cats.

Russell Kellett, 40, of Filey, has spent years compiling what he claims to be one of the country's largest databases of paranormal activity, including alien craft sightings, abductions, haunted houses and crop circles.

He is interested in cyptozoology - the study of unknown species of animals like the abominable snowman and the Loch Ness Monster and after moving to North Yorkshire three years ago has become fascinated by the "Beast of Ryedale".

During the past six months there have been dozens of reports of encounters with and sightings of large cats similar to a puma or jaguar - from places ranging as far as Selby, Acomb and Castle Howard.

"When the Dangerous Animals Act came into force in the 70s people who owned these animals as pets, rather than register them just let them go. One school of thought is that there are a number of big cats roaming the UK," he said.

"There has been evidence of their existence, like sheep and cattle that have been found dead with huge bite marks - if it wasn't big cats, what was it?"

Mr Kellett's interest has been particularly aroused by a recent report, which was condemned as rubbish by Ryedale area commander Inspector Neil Burnett, of the body of a big cat killed on the A169 Pickering to Whitby road being removed by police.

"I'm interested in hearing from anybody in Ryedale that may know anything about this recent story of the body of a big cat being found, or if anyone has seen one or has evidence or footage."

Mr Kellett claims to have had a brief encounter with an alien craft 14 years ago when he was fixed in a beam of light and later saw a UFO.

"I had a close encounter with a strange object. That's when my illness started and so did my quest for the truth," he said.

The paranormal investigator believes he now suffers from the debilitating disease myalgic encephalomyelitis (ME) because of the experience.

He has since filmed footage of mysterious balls of light, flying triangles and strange rods in the sky.

Mr Kellett and his footage have appeared on several television programmes, including a BBC documentary, and in magazines.

He can be contacted through his online magazine www.ufoparanormal.com or by e-mailing rkellett@supanet.com or on the UFO hotline 01723 514700.

Updated: 14:35 Tuesday, March 08, 2005