Nick Harding from London Fire Brigade said the audience at the Apollo Theatre were walking around in a dazed condition after the ceiling collapsed.
The Kingsland Fire Station manager said, "People were in a lot of shock ... a lot of them had head injuries and other injuries so it was quite a confused scene."
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Expect a bright day today with plenty of winter sunshine and clear blue skies across the country.
Clear skies allowed a satellite image to be taken, showing snow in the Pennines, north Midlands, Northern Ireland and Scotland yesterday.
Molly Smith, 5, won £500 after her accidental selfie with a snowman caught the attention of competition judges.