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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Any early mist and fog will soon clear. Plenty of warm sunshine will develop.
Dry and often sunny once any morning mist and low cloud clears. Warm inland, but cooler along coasts.
The pair were found guilty of running a number of brothels and trafficking vulnerable Chinese and Malaysian women around the country.