A lorry fire close to the M4 tolls has closed the motorway leaving drivers being diverted over the M48 Severn Bridge.
Initially the westbound carriageway was closed, but Traffic Wales says the motorway is now closed in both directions.
South Wales Fire Service says it was called at around 12:47pm and has requested assistance from the Avon and Somerset service. The fire is understood to involve a large quantity of hay.
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