Nicola Morgan MP described to ITV News how she heard an "almighty bang" and saw "clouds of thick black smoke" as she walked towards Vauxhall tube station.
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Downpours keeping us on our toes today
The M20 in Kent has been closed in both directions after a pedestrian bridge allegedly collapsed on the motorway on Saturday.
The AA have warned of traffic jams and urged people to carry extra water in their vehicles because of the warm weather.