A writer who was at London's Apollo Theatre when the ceiling collapsed said he saw "a lot of kids traumatised, covered in dust and blood being comforted by parents".
The Independent features writer Simon Usborne told Daybreak: "There were screams, it was immediately clear something serious had happened.
"Nobody told anyone to move - everybody rose immediately and ran to the nearest exit".
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Special forces launched an early morning raid on Thursday to drive the so-called Islamic State away from a key military base.
The Government has faced repeated calls to suspend arms sales to Saudi Arabia after "repeated and serious breaches" of alleged abuses.
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