Firefighters spent all day tackling a huge blaze at a former hospital following a suspected arson attack.

Fire crews were called to the old St Andrew’s Hospital in Thorpe St Andrew at around 5am today.

At its height seven fire engines, an aerial ladder platform and 42 firefighters were at the site.

Ian Mackie, the county councillor for Thorpe St Andrew, said the fire follows a "familiar pattern". 

Norwich Evening News: The arson was reported to police at 5.38amThe arson was reported to police at 5.38am (Image: Newsquest)

Norwich Evening News: Police are appealing for witnessesPolice are appealing for witnesses (Image: Norfolk Constabulary)

"This is another fine and historic building lost, having already been heavily damaged over many years of neglect," he said. 

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"This follows fires at the Oasis, Little Plumstead Hall, Langley School, the Griffin Pub and of course Pinebanks.

"It’s now sadly an all too familiar pattern, an old or listed building is on a site for development and it comes to a tragic end.

Norwich Evening News: Fire crews are tackling a blaze at the old St Andrew’s HospitalFire crews are tackling a blaze at the old St Andrew’s Hospital (Image: Newsquest)

"Any empty building is always at risk, that’s why I would support any steps to ensure owners have a duty to protect historic assets and there’s a reduction in land banking, often for decades at a time.”

In December 2016 the Lind Trust was given outline planning permission for 12,750sqm of office space on the site by Broadland District Council, involving part conversion of existing buildings and part redevelopment of the site into a business park.

But the site to the north of Broadland Business Park has remained derelict.

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The main building on the site, St Andrew's House, was originally an addition to the Norfolk Lunatic Asylum to the south of Yarmouth Road, being completed in 1881.

The whole site was closed as an NHS hospital in April 1998.

A spokeswoman for Norfolk County Council said the building is an unsafe structure and police are leading the investigation. 

Nobody is believed to have been injured in the fire and a police cordon will remain in place while investigations continue.

Anyone with information is urged to contact PC Ben Leach at Norfolk Constabulary on 101 or via email: quoting reference 36/74585/23.