At least five people have died after a volcano erupted in New Zealand.
Police said the number of people missing is in double figures as they try to rescue up to 50 people from White Island, which is uninhabited but frequented by tourists.
They earlier confirmed that 23 people had so far been rescued, with some of those transferred to hospital with “severe” burns.
Police Deputy Commissioner John Tims added they still do not know an exact number of people involved in the incident, but both New Zealanders and international tourists are thought to be involved – thought to be from the Ovation of the Seas cruise ship.
Mr Tims also said that it is too dangerous to search the island following the eruption so a rescue operation has been suspended on advice of experts.
An earlier statement from St John Ambulance said it had dispatched paramedics on helicopters, and was aiming to establish a triage unit on the island.
The New Zealand Defence Force has also been dispatched to the area to help emergency services.
The eruption began at about 2.11pm local time.
Officers are hoping to locate the people who are unaccounted for through the passenger list from the cruise ship where many of the tourists had come from.
They added that they do not expect any significant impact on New Zealand’s North Island, one of the country’s two main islands, which is about 30 miles (50km) west of White Island – also known by the indigenous Maori name Whakaari.
Earlier, Prime Minister Jacinda Ardern said the incident appeared to be “very significant”.
“A number of people are reportedly injured and are being transported to shore,” she said.
The GeoNet agency said a moderate volcanic eruption had occurred, throwing smoke and debris about 12,000ft (3,660m) into the air, and raised its alert level to four, on a scale where five represents a major eruption.
Dr Ken Gledhill, technical adviser at GNS Science, said it was “not a particularly big eruption” and was “almost like a throat clearing kind of eruption which is why material won’t make it to the mainland”.
“For volcanic eruptions it’s not large but if you were close it’s not good,” he added.
“It’s shown increased activity over the past few weeks so we raised the alert.
“We can’t be certain there won’t be another eruption in the next 24 hours.”
There will be questions asked as to why tourists were still able to visit the island after scientists recently noted an uptick in volcanic activity.
Royal Caribbean, whose cruise ship was visiting the mainland, had passengers on an excursion to the volcano.
A spokesperson for the company said: “We can confirm that a number of our guests were touring the island today. We do not have any additional details to share at this time.”
Police have told people to avoid areas on North Island that are close to the eruption, including the Whakatane Heads and Muriwai Drive areas. A no-fly zone has also been established.
Footage from the scene shows walls of ash and smoke rising from the island, as well as a helicopter damaged in the eruption, laid on the ground.
White Island is New Zealand’s most active cone volcano and about 70% of the volcano is under the sea.
Twelve people were killed on the island in 1914 when it was being mined for sulphur. Part of a crater wall collapsed and a landslide destroyed the miners’ village and the mine itself.
The remains of buildings from another mining enterprise in the 1920s are now a tourist attraction, according to GeoNet.
The island became a private scenic reserve in 1953, and daily tours allow more than 10,000 people to visit the volcano every year.