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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Actor Michael Nyqvist, famed for starring in the original film adaptation of The Girl With the Dragon Tattoo, has died aged 56.
Some 13% of the average UK adult's salary is spent paying basic domestic bills, which is an average total of £524,464 over a lifetime.
The Crown Prosecution Service is to announce its decision later on whether individuals and organisations will face criminal charges.