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."
More top news
Parts of the UK will feel colder than the Arctic Circle in the coming week as bitter winds make it feel -15C in some places.
At least three people have been killed in clashes in eastern Ghouta just hours after the UN Security Council backed a 30-day ceasefire.
Very Very Cold !