Loughborough MP Nicky Morgan says she "heard an almighty bang" and "saw clouds of thick black smoke" as the helicopter crashed into a crane in South London this morning.
The MP was walking towards Vauxhall tube station, when the accident happened.
"Ms Morgan says she "saw clouds and clouds of thick black smoke billowing from the ground" and that initial thoughts were that a bomb had exploded."
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After a wet and windy start to Tuesday, rain will clear to the north to leave it dry, with easing winds but largely cloudy skies.
Early rain will clear northwards during Tuesday morning, allowing drier conditions behind.
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