A powerful explosion has damaged a building in the centre of the Czech capital Prague, the Associated Press reports.
Police spokesman Tomas Hulan said it is not immediately clear what caused the blast and it is believed some people are buried in the rubble.
At least 13 people have been injured, fire service spokeswoman Pavlina Adamcova said.
Windows in buildings located hundreds of metres from the blast were shattered, including some in the nearby National Theatre.
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