A large fire that destroyed staff accommodation above a popular pub was started by a faulty tumble dryer, investigators say.

Thirty five customers and eight members of staff were evacuated from The Castle pub, in West Street, Harrow-on-the-Hill, as the fire quickly spread on Easter Monday.

More than 30 firefighters were involved in tackling the blaze, which took almost two hours to extinguish and left the second floor of the three-storey building severely damaged.

No-one was injured, but one member of staff was treated by paramedics for smoke inhalation.

Investigators have since traced the source of the fire to a tumble dryer in the upstairs staff accommodation.

Fuller’s brewery, which owns the pub, said it would not comment on how many staff members lived in the building, but said it would be working with the London Fire Brigade to investigate how the tumble dryer caught fire.

Meanwhile, staff have described the “surreal” scenes as dozens of people were evacuated when the fire alarms went off shortly after 5pm on Bank Holiday Monday.

One representative of the management team, who has worked at the pub for the past three years but did not want to be named, said: “It was just a case of getting everyone out as quickly as possible.

“We carry out staff evacuation drills almost every week but to do it and for it to be real was very strange. The whole thing was just very, very surreal.”

Firefighters were praised for their hard work tackling the blaze in what Harrow Fire Station manager Simon Tuhill described as intense heat and challenging conditions.

Many people took to Twitter to express their dismay at the pub fire and support the popular venue.

Harrow West MP Gareth Thomas wrote: “Glad to see the Hill's great Castle pub wasn't more damaged by yesterday's fire. One of Harrow's best.”

Neighbours have also been praised for their help during the incident, with many providing refreshments for firefighters and staff.

The pub’s management team added: “We want to say thank you to everyone who helped out on the day.

“Everyone was so nice, bringing out tea and coffees and food for the firefighters. The reaction on Twitter has been amazing to see – we didn’t realise exactly how much people like us.”