M4 shut in both directions after crash as air ambulance lands at scene - live updates

A multi-vehicle accident has shut the M4 completely this morning. According to traffic monitoring service Inrix, the incident has taken place westbound between J42 A483 Swansea East / Briton Ferry to J44 A465 Llandarcy in Neath Port Talbot.

An air ambulance is at the scene and congestion is now reaching to J41 in Baglan/Pentyla westbound. At around 11am, Traffic Wales confirmed that M4 eastbound's carriagway had been reopened.

South Wales Police has warned that the road is expected to remain closed for "some time". In a statement, they said: "We are at the scene of a collision on the M4 between Junction 42 and 44.

They added: "It is expected to remain closed for some time. Motorists are advised to avoid the area and use alternative routes where possible. Delays are expected in the area."

Follow our live updates on the incident below: