Four people were killed as a powerful explosion destroyed a building in the English city of Leicester, police said today.

Police declared a "major incident" after the explosion occurred last evening on a stretch of road containing commercial and residential properties in Hinckley Road area of Leicester, a city with a large Gujarati-origin population. Leicester is over 143 km away from London.

Four people were killed in the explosion and subsequent fire that destroyed a shop and the flat above it, police said today.

Earlier reports said six people were taken to hospital after the Two of the injured are stated to be in critical condition.

A fire and rescue service spokeswoman said the emergency services were conducting a search and rescue operation and it was unclear if people were trapped in the rubble.

British police said there was no indication the explosion

was linked to terrorism.

"The cause of the explosion will be the subject of a joint investigation by the police and Leicestershire Fire and Rescue Service," police said in a statement.

"We would ask that the media and public do not speculate about the circumstances surrounding the incident, but at this stage there is no indication this is terrorist related," it said.

The emergency services said they were called to reports of a blast shortly after 7 pm (local time) and six fire engines were sent to the scene, the BBC reported.

A fire service spokeswoman said the property was a two-floor building with a loft conversion that had suffered a "pancake collapse".

The emergency services have cordoned off about 60 houses in the area, which was a mix of apartments and small shops, including a convenience store, a kebab restaurant and a Polish grocery.

Eyewitnesses said there was thick smoke in the area. One neighbour told BBC she heard "this big thud, like an earthquake."

"The building had gone down and people were trying to help where they could by taking the bricks off. But the fire was getting bigger and bigger so people were told to leave the scene," she said.

She said she and others helped a boy, believed to be aged about 15, who was hurt in the blast.

"He was in there when it happened. I think he was in the flat above the shop. We were keeping him warm and assuring him he'd be OK and the ambulance would be there," she said.