Firefighters are battling a major blaze involving a lorry on the M4.
The road is closed in both directions due to heavy smoke across both carriageways between junctions 15 and 16.
It’s not yet clear if anyone’s been injured as a result of the fire.
At least one lane of the M4 westbound is likely to be significantly damaged by the blaze which will probably result in lane closures over the next 24 hours.
The road is expected to reopen by 5pm.