Six people have been taken to hospital after an explosion destroyed a shop in Leicester.
Police declared a “major incident” after reports of a blast in Hinckley Road just after 19:00 GMT on Sunday.
A police spokesman said: “At this stage there is no indication this is terrorist related.”
Two of the six in hospital are in critical condition and the others are “walking wounded”, said the University Hospitals of Leicester NHS Trust.
Carlisle Street and part of Hinckley Road have been closed and people are being asked to avoid the area. Electricity has been cut off for a number of properties.
Angel Namaala lives opposite the shop, believed to be a convenience store, and told the BBC she had 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.
Leicestershire Police said: “The cause of the explosion will be the subject of a joint investigation by the police and Leicestershire Fire and Rescue Service.”
Six fire engines were sent to the scene and a fire service spokeswoman said crews were involved in a “search and rescue” operation.
The property was a two-floor building with a loft conversion that had suffered a “pancake collapse”, she added.
All of the casualties have been taken to Leicester Royal Infirmary and people have been asked not to attend A&E unless “absolutely necessary”.
BBC journalist John Alexander said the emergency services had cordoned off about 60 houses in the area.
“I live about 80 yards away from where it happened,” he said. “I felt a tremor, what felt like an earthquake shock and I heard a very low boom that sounded like a very, very fast release of pressure.
“I thought my house was going to fall down on top of me and all my neighbours have said the same thing.”
Alpana Marwaha, who lives near the scene, told the BBC: “I heard a bang and the house shook. We could see the flames.
“You can still see the smoke coming, and the emergency services. There are a few shops there and it is surrounded by houses.”