An investigation has been launched into a fire feared to have put dozens of people at risk from asbestos.

At its height, 50 firefighters tackled the blaze at a former social club near St Leonards Warrior Square railway station.

At one point the roof of the building, which has been empty for 18 months, collapsed and a gas cylinder inside exploded and blew down one of the walls.

Asbestos from the derelict single-storey building thrown up by the blaze settled on up to 250 houses, flats and gardens.

Warning letters were delivered to people's homes in the early hours of yesterday while the fire was raging, telling them to stay inside and keep their windows and doors shut.

Later, council officials confirmed the dust was asbestos but said it was low grade and people were not at risk.

Commuters faced chaos throughout the day because the station and St John's Road were closed while the area was checked for asbestos and the damaged building made secure.

Trains did not stop at the station and a bus service ferried passengers between St Leonards and Hastings.

Trains were also subjected to delays and cancellations, although the station was reopened to commuters just before 2pm yesterday.

A South Eastern Trains spokesman said: "We apologise for any inconvenience to passengers but we had to do this as a precautionary measure while the work was being done."

The fire started shortly after 9pm on Sunday and was under control just before midnight.

It was still smouldering early yesterday and fire crews and investigators were at the scene for most of the day.

British Transport Police are also investigating the fire, which is believed to have been started deliberately.

Engineers pulled down a dangerous section of the building to make it safe for investigators to enter. Specialist asbestos cleaning teams cleared both the building and the surrounding homes and streets.

A council spokesman said: "People can still go out and about but we are still advising them to keep the windows and doors closed for now."

The fire sparked memories of the blaze at the former Broomgrove power station in May 2000, which left hundreds of residents fearing asbestos contamination.