In a statement, the Prime Minister of the Czech Republic Petr Necas said he was "deeply hit by the tragedy of the gas explosion", the Associated Press reports.
It is not certain what caused the blast in Divadelni Street in the central Prague but it was likely to be a natural gas explosion, police spokesman Tomas Hulan said.
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Tonight it'll stay wet across northern areas of Britain, with further showers pushing into the South West.
A boy who has spent three years caring for his older brother after he was injured falling off a motorbike has been honoured by Prince Harry.
This week will be more changeable with the remnants of ex-hurricane Joaquin heading towards the UK, bringing wet and windier conditions.