More than 60 fire fighters tackled an inferno at a former tannery in Otley last night.

About 20 residents from ten houses were evacuated during the blaze at the four-storey building which was in danger of collapsing.

The remaining part of the building on Gay Lane burst into flames at about 7.40pm. The fire, which is being investigated, is the second at the building this year.

At its height there were 14 fire engines and support vehicles at the scene.

A crowd watched as police officers evacuated all the residents from a row of cottages which back onto the derelict building.

One of the evacuees, Michael Crooks, 38, happened to look out of his back door when the building went up in flames.

He said: "I just couldn't believe what I saw just at the back of my house. I went straight on the phone and dialled 999.

"I saw flames going through the roof, then it caved in. It took hold very quickly and I heard glass exploding.

"Then police came and told us to get out until it was under control. They were worried it might collapse.

"The building is about 30 feet away from my house."

"This building has been on fire before and half of it was pulled down after the last fire.

"We have had so many arson attacks in the last few months in Otley, everybody is getting very worried about it."

The land is believed to be owned by supermarket chain Sainsbury's. The company is thought to be applying for planning permission to build a store there.

Firefighters used seven hoses and several hydraulic platforms to fight the blaze in the 80m-by-45m building.

Divisional fire officer David Wilkinson, the incident commander, said: "Most of the floors have been heavily hit by fire and it was well alight when we first got there.

"Parts of the building were in danger of collapse and there was an exposure risk to some of the cottages close by".

Firefighters remained at the scene until 10am today damping down.

Residents were evacuated for two hours until a structural engineer from Leeds City Council said it was safe for them to return.

Gay Lane was closed for two hours from the Junction pub on Chevin Road.