At least five people are dead with tourists among a number of others left unaccounted for as a volcano erupted in New Zealand with about 50 people in the vicinity.

Visitors were seen walking inside the rim of the White Island crater just moments before the eruption.

Police said at least one of the 23 evacuated from the island was critically injured and the number of fatalities was likely to rise.

White Island, or Whakaari, off the coast of North Island, is one of the country’s most active volcanoes yet attracts frequent day trips and scenic flights.

One group and a crew member from Royal Caribbean International ship Ovation of the Seas were reported by the New Zealand Herald to be on the island at the time of the eruption.

Royal said Ovation of the Seas will remain in port as long as it is needed to assist with the situation.

In a statement, the cruise line said: “We are devastated by yesterday’s events and our hearts go out to all those affected by this tragedy.

“We are working together with local authorities, and we are providing all the help and care we can to our guests and their families, including offering medical resources and counselling. We are also sending staff members from both our ship and our Sydney and Auckland offices to assist family members however possible.”

Visitor Michael Schade, who was on a boat leaving the island, filmed the eruption, showing a thick plume of ash and smoke above the mountain.

A live feed from the volcano showed a group of visitors inside the crater before images went dark after the eruption.

Another group of tourists can be seen waiting to be rescued from the island, according to the BBC.

The eruption started at around 2.11pm local time.

New Zealand Police said: “While it was initially believed there were approximately 100 people on or near the island at the time of the eruption, we now believe there were fewer than 50.

“Some of those people have been transported to shore, however a number believed to be on the island are currently unaccounted for.

“Of those transported to shore, at least one has been critically injured.

“Emergency services are working to ensure the safety of everyone involved, including rescue staff.”

The FCO has updated its travel advice: “The Whakaari/White Island volcano erupted on 9 December. An emergency response is under way. If you are travelling in the area, you should follow the advice of the local authorities and / or your tour operator.

“If you’ve been affected by the incident and need urgent consular assistance, you should contact the British High Commission in Wellington on +64 (0) 4 924 2888. If you are in the UK and you’re concerned about friends or relatives in the area, you should contact the FCO in London on 020 7008 1500.”

Around 200,000 British nationals visit New Zealand every year.