businessman Charlie Deuchar ended up fighting a fire clad only in his underpants as a pile of blazing cardboard threatened to set fire to the second oldest building in Dartmouth.

Meanwhile, one hotel guest, still in her pyjamas, and Charlie's wife Zuzanna used wine coolers full of water to make sure the fire, outside the centuries old timber-framed Bayards Cove Inn at Agincourt House in Lower Street, was completely out.

The fire, which is thought to have been caused by a discarded cigarette, cracked windows, damaged wooden window frames and wrecked a wooden sign outside the cafe, tapas bar and hotel.

Charlie, who has run the business with Zuzanna for the last six months, said that at one point the flames were licking six or seven feet up the front of the building.

'We were very, very lucky. It really is terrifying to think of what could have happened,' he said.

The blaze was spotted at around 2am on Monday morning after a Bristol couple staying in a room directly above the fire smelled smoke and looked out.

'They were just going to bed and they thought they could smell something like candles and looked outside,' said Charlie.

'They saw the flames licking up the front of the building directly below their bedroom. We were in accommodation at the back and they came around shouting "fire".

'I came running out in my pants and found a bonfire with flames six foot high right outside the front window.

'I put it out with a fire extinguisher and called the fire brigade.

'They were amazing. They were here in five or six minutes. They were so quick.

'The fire brigade think it is very likely that it was a cigarette butt.'

Zuzanna said guests had helped ensure the blaze was out by filling up wine coolers with water and pouring them over the smouldering cardboard. The couple were so grateful to the guests they have given them a free stay as a thank you.

The pile of flat packed cardboard outside the Bayards Cove Inn had been left out for a recycling collection on Monday morning.

Charlie urged smokers to be more careful with what they do with their cigarette butts.

'People really need to be more careful and particularly don't flick their cigarettes into a pile of cardboard,' he said.

Agincourt House dates back to 1380 and is believed to be the second oldest building in Dartmouth, said Charlie.

The building is owned by Dartmouth hotelier Nigel Way who suffered a massive fire disaster three years ago when the Thai restaurant complex he owns was wrecked in a blaze which gutted a whole block of flats, businesses and offices.

That building has only just been restored at a cost of more than £1m.