UPDATE 8.10pm: Both lanes are now reopen, though tailbacks continue to cause delays.

UPDATE 7.11pm: Multiple vehicles are on the hard shoulder and a lorry is blocking both lanes.

South Wales Argus:

UPDATE 7.06pm: Two lanes remain closed, there is queueing traffic for 5.6 miles due to multi-vehicle accident on the M4 Prince of Wales Bridge westbound.

Two lanes of the M4 are closed westbound following a crash.

Traffic officers are heading to the scene but delays are expected.

South Wales Argus:

The incident, between Junction 22 and Junction 23 of the M4 Westbound, has closed lane 1 and lane 2.

Tailbacks are causing severe delays of up to 60 minutes according to Traffic Wales.