A Norwich couple in Bali are being briefed on emergency procedures amidst fears of a major volcanic eruption on the island.

Norwich Evening News: Norwich couple Callum Edwards and Evie Wolltorton are on holiday in Bali, where a major volcanic eruption is expected. Picture: Callum EdwardsNorwich couple Callum Edwards and Evie Wolltorton are on holiday in Bali, where a major volcanic eruption is expected. Picture: Callum Edwards (Image: Archant)

Callum Edwards, 32, and Evie Wooltorton, 22, have been on holiday in Kuta and are staying within 70k of Mount Agung, which has been spewing thick ash cloud into the atmosphere since the weekend.

Indonesian authorities have now raised the state of alert to its highest level after continuous ash puffs and weak booms were recorded.

The international airport has been closed, meaning thousands of tourists are now stranded on the island.

Mr Edwards and Miss Wooltorton are only halfway through their holiday, however, the airport is not expected to reopen imminently.

Mr Edwards said he was satisfied that adequate safety measures are in place in case of an emergency.

He said: 'I'm currently not too concerned, we're being kept up to date with events from the hotel and local authorities.

'We are approximately 70km from the volcano and there are safety measures in place in case of an emergency happening locally here.'

Around 100,000 people have been evacuated from the volcano's surrounding areas as the danger zone has been expanded to as far as 10k.

Dark ash clouds have billowed up to 3,400m above Mount Agung's summit, with lava welling up in its crater.

Ash has already settled on villages and resorts around the volcano and soldiers and police have distributed masks in the affected areas.

Videos released by the National Disaster Mitigation Agency showed a mudflow of volcanic debris and water known as a lahar moving down the volcano's slopes. The agency warned lahars could increase because it is rainy season and people are being told to stay away from rivers.

Mount Agung's alert status was raised to the highest level in September following a dramatic increase in tremors from the mountain, which prompted more than 140,000 people to leave the area. The alert was lowered on October 29 after a decrease in activity but about 25,000 people remained in evacuation centres.

The volcano's last major eruption in 1963 killed about 1,100 people.