MOTORISTS are being warned of heavy and slow traffic on the M5 after black smoke was said to be blowing across it.

The northbound carriageway between junction 20 for Clevedon and junction 19 for Portishead shut earlier this morning.

It is thought a crash took place which led to a car fire, and police shut the road due to smoke causing visibility problems.

The road has reopened but warnings of heavy and slow traffic are still in place.