The is closed eastbound near London Heathrow Airport following a multi-vehicle crash. The motorway is currently shut between J4 and J3 (Hayes) while pictures of the area show heavy traffic.
The Metropolitan Police, London Fire Brigade and National Highways traffic officers are at the scene of the crash which saw one car overturn and rest on its roof.
There was also a seprate incident in Wales which has caused major delays on the M4.
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