Residents have been evacuated from nearby properties following a suspected gas explosion in a flat above a shop.
The blast tore through walls and doors in the building in Cannock Road, Chadsmoor, Cannock at about 10:50 GMT.
A man inside the Select and Save convenience store was taken to hospital and treated for shock, Staffordshire Fire and Rescue Service said.
The explosion blew the walls and doors out by about 1ft (30cms) in some parts of the flat, it said.
Ian Housley, from the fire service, said: "There is a day nursery next door but, thankfully, being Sunday, there was no one about."
He described the damage as severe and said: "The pressure, like a wave, has come through the back of property and up, removing all the tiles and gable end and roof making it quite unstable."
A building inspector is assessing the site and gas and electricity company workers are making sure the area is safe.
"Residents have been allowed back into their properties but next door will have to be rehoused because it is just too dangerous and too close to the building itself," Mr Housely said.
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