Two youths are being questioned by police following a fire at a derelict water tower in Sheerness on the Isle of Sheppey.

Flames and dark billowing smoke were seen coming from the building in Trinity Road just after 4pm this afternoon. Visitors to a fun day in the former council offices next door had to be evacuated.

Three fire crews, two from Sheerness and one from Sittingbourne, fought the blaze and took additional water from a hydrant across the road which led to traffic delays.

Kent Fire and Rescue spokesman Dean Firmin, station manager at Maidstone, said: "We sent a two-man crew with breathing apparatus into the building. At that stage we didn't know if anyone was still trapped inside. It was very dark and dangerous. We had no idea of the state of the floors inside."

He warned: "It is very dangerous to play in buildings like this. You can injure yourself and also put my firefighters at risk. Today also caused disruption to the town."

Unconfirmed reports said that the building is used by two homeless men to sleep in.

Eye-witness Martin Jones, 61, said: "I saw the smoke from my friend's flat. I don't know how it started."

Film-maker Lance Phillips, 45, from Chatham, was filming next door for the Sheerness Enhancement Association for Leisure fun day when the fire broke out.

He said: "I heard someone shouting fire and ran out and saw smoke billowing from the open windows on the side of the building. I understand two youngsters were in the building and ran off. But it appears they returned and were stopped by the police.

"It was a real shame because we had to close the fun day early. During the blaze everyone was evacuated from Masters House."

A police spokesman said: "Kent Police was called to a report of a building fire at 4.15pm on Saturday 16 July in Trinity Road, Sheerness.

"Two boys have been arrested in connection with the incident and are in custody."

Inquiries are ongoing.