Homeless people are believed to have started a fire to keep warm while sleeping in an underground car park causing a fire alarm to go off.

Firefighters were called to St George’s House, in St George’s Road, Wimbledon, at about 11.30pm last night, where they found a large quantity of recycled paper and rubbish burning.

The smoke had set off an automatic fire alarm and three fire engines arrived on the scene – two from Wimbledon and one from New Malden.

It is believed rough sleepers had collected rubbish from nearby shops in Wimbledon town centre.

A Wimbledon firefighter said: “We managed to quickly contain and extinguish the fire before it caused damage to the structure.

“They had moved on before we arrived but it was obvious there had been vagrants there.

"It’s not something we usually see in Merton and it’s more common in central London.”

Last year, official Government figures estimated there were only two rough sleepers in the borough, but a Wimbledon Guardian investigation found the true figure was up to 10 times bigger.

Rough sleepers of eastern European origin have been well documented and are often reported in Tooting, Mitcham and Colliers Wood.