The M5 was closed southbound between Wellington and Tiverton on Sunday evening after a multi-vehicle crash in thick fog, with one vehicle ending up on its roof.

The crash happened at about 6pm near junction 27 for Tiverton, on the Devon and Somerset border. Up to eight vehicles were believed to have been involved, and all traffic on the southbound carriageway was stopped as far back as junction 26 for Wellington.

National Highways reported delays of up to 50 minutes and tailbacks of around five miles while emergency services dealt with the scene. At least two lanes were shut so that vehicles could be recovered, and dashcam footage showed a vehicle upside down on the carriageway.

Drivers caught behind the closure were expected to be held for up to an hour before they could be directed onto other roads. One early estimate put the reopening at about 9pm, with later estimates suggesting the road could clear by 8.45pm. All lanes were eventually reopened, although residual traffic remained on the southbound carriageway into the night.

The reports available did not give a confirmed number of people hurt in the crash. Emergency services attended the scene, and the carriageway had to be cleared before traffic could move again.

The crash came as thick fog settled across the West Country. The Met Office had issued a yellow weather warning for fog from 6pm on Sunday until 11am on Monday, covering large parts of England and Wales. Forecasters warned that fog patches would become extensive overnight, with visibility as low as 50 metres in some places, and that drivers should switch on fog lights, allow extra time and check road conditions before travelling.

National Highways traffic cameras at Wellington's junction 26 showed the foggy conditions on Sunday night. The Met Office said the warning area was not expected to spread south of Taunton, but fog was forecast to linger into Monday morning before slowly thinning.

The incident was first logged at 18.37, and the carriageway was clear again after about two and a half hours, according to live motorway incident records. By then, long queues had built up on the approach to the closure, and drivers who had been diverted onto local roads faced slow journeys through the fog.

The Met Office warning covered a wide area, including the East Midlands, the East of England, the South West, Yorkshire and the Humber, the West Midlands, Wales, the North West, the South East and London. It was the second yellow fog warning issued in 24 hours. Forecasters said delays to buses and train services were possible, with flight cancellations also on the cards, and warned that fog would become extensive by Monday morning. Met Office meteorologist Tom Morgan said fog was set to be 'quite heavily in the forecast through this weekend and for some of us into next week, too'.

Motorists heading south-west on Sunday night were advised to expect delays and to allow extra time for their journeys while the fog warning remained in force.