A fire which ravaged a property in Norwich city centre is being treated as arson, police have confirmed.

Norwich Evening News: Police are still on the scene at a fire which tore through a three storey house in Coslany Street, Norwich. Picture: staffPolice are still on the scene at a fire which tore through a three storey house in Coslany Street, Norwich. Picture: staff (Image: Archant)

An investigation is under way after fire tore through a three-storey house in Coslany Street house in Norwich on Saturday.

Brave passers-by kicked in the front door in a desperate attempt to discover if there were people trapped inside.

After the fire broke out, at about 2pm on Saturday, fire crews from Earlham, Carrow, Sprowston and Hethersett attended to extinguish the blaze.

A fire service investigation has begun into what started the fire although no cause has yet been confirmed.

Norwich Evening News: Fire on Coslany Street in Norwich. Photo: Simon ParkinFire on Coslany Street in Norwich. Photo: Simon Parkin (Image: Archant)

However, police have confirmed the incident is being treated as arson.

A spokesman said: 'We are treating the fire in Coslany Street on as arson and investigating.

'We would ask that anyone who may have seen anything or have any information contacts Sgt Chris Claydon at Bethel Street Police Station on 101. Alternatively, they can call Crimestoppers anonymously on 0800 555 111.'

No-one was inside the property at the time of the fire but it has since emerged that the house was a popular haunt for 'crackheads'.

Leona Whitworth, 23, who lives in nearby Barnard's Yard, claimed: 'That's where all the crackheads and smackheads go'.

A 58-year-old woman living near to the city council-owned property, who did not want to be named, said 'It has been a bit of a drugs den before.'

A woman in her 60s, who did not want to be named, said there had been problems associated with the property for years during which time there had been three or four 'drugs raids'.

Michael Markou, 44, has since told how he ignored his own safety and ran into a burning building - wearing flip-flops and shorts - because he thought there were people trapped inside.

He said: 'The only thing that went through my mind was that there might be people in there. I couldn't stand there and watch it burn.'