Emergency patients have been urged to avoid using the A&E unit at Whipps Cross hospital as east London is hit by severe flooding.
Torrential rain has led to flash flooding in parts of London and the South and the Met Office has issued an amber storm warning.
An announcement on the website of Barts Health NHS Trust says Whipps Cross and Newham Hospitals are experiencing "severe operational issues" and asks patients to go to "alternative A&Es" if they need urgent care.
A screengrab from the Barts Health website
Streets have been left underwater in Walthamstow and areas around Newham, Hackney Wick and Barking have been affected.
Pictures and videos have been posted on social media showing cars stranded and struggling to make their way through the flooding.
One person posted a picture of what appears to be a gigantic crack in the middle of a road captioned “It just rained so hard in Walthamstow the street exploded”.
Read more: Major flooding in Walthamstow as torrential rain causes 'street to explode'
There are major delays on the A406 with several stretches of the carriageway underwater.
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