A bizarre fire in which a dust sheet spontaneously combusted in a couple's living room but failed to set anything else alight has baffled homeowners and firefighters.

George and Eileen Mower, who are decorating their house, couldn't believe their eyes when they found the white dust sheet on their living room floor had turned to black ash overnight.

Mr Mower said: "It's absolutely bizarre. We just can't believe it.

"The fire actually burnt round a plastic bag full of wallpaper that was on top of the sheet. It's like something from the X-Files. I'm thinking of calling Mulder and Scully."

The couple had laid the sheet down on Saturday before peeling off layers of old wallpaper and scrubbing down paintwork.

They used no chemicals or white spirit and are mystified as to what caused the sheet to ignite of its own accord.

Apart from singeing the carpet the incident caused no smoke or fire damage to anything else in the room.

Mr Mower, 59, said: "It's a bit spooky.

""I was up three times in the night and even let the dogs out so I was walking right past the door.

"It didn't set the fire alarm off. I didn't smell anything and the dogs can't have either."

When they discovered what had happened, Mr and Mrs Mower called out the fire brigade to see if they could unravel the mystery blaze.

But officers were just as perplexed.

Fire investigation officer Duncan Voice said: "I've been doing this job for 15 years and I've never seen anything like this. It was a very unusual fire. It appears to be some sort of self-heating fire but what caused it I just don't know.

"There's no obvious ignition source. It's very peculiar."

He said samples from the remains of the sheet would be sent away for chemical analysis to see if that could determine the cause of the fire.

Mr Mower said: "I just can't figure out why the fire didn't take hold.

"This should have destroyed the front room and the repercussions of that are even more scary."

The couple, who have lived at their home in The Crescent, Southwick, for the last ten years, said they had never experienced any paranormal activity.

Mr Mower joked: "I've never seen any ghosts but I'm going to get my telescope out tonight and start looking for flying saucers."

However, Mr Voice said: "There's definitely a scientific explanation.

"I just don't know what it is yet."