Eight people were still missing after a volcanic eruption in New Zealand, with no indications they survived the explosion that has already left five dead, police said Tuesday.

After initial confusion about how many people were visiting White Island when it erupted unexpectedly on Monday, police said a clearer picture of the disaster was emerging.

“Forty-seven people went onto the island — we can now confirm five are deceased, 31 are currently in hospital, a further eight are still missing and three have been discharged from hospital,” police official Bruce Bird said.

Among the missing are tourists from Australia, the United States, Britain, China and Malaysia, as well as New Zealanders who were acting as tour guides.

New Zealand Prime Minister Jacinda Ardern offered condolences on behalf of the country.

“To those who have lost or are missing family and friends, we share in your unfathomable grief and in your sorrow,” she said.

“Your loved ones stood alongside Kiwis who were hosting you here and we grieve with you.”

Bird said a helicopter has scoured the island — a popular tourist attraction — for 45 minutes, checking if anyone was still alive.

“We do not believe anybody else has survived that explosion,” he said.

Police will assess whether a recovery mission to remove bodies from the island is possible Tuesday amid the risk of further eruptions.

“Today our focus will be on working with experts to determine the safety for us to return to the island to look to recover those people who are currently missing,” Bird said.

“We will only go to the island when it is safe to do so for our people.”

What happened at the volcano?

White Island, also called Whakaari, is the country’s most active volcano. Despite that, the privately owned island is a tourist destination with frequent day tours and scenic flights available.

The volcano erupted in two explosions in quick succession at around 14:11 (01:11 GMT) on Monday, sending up a thick plume of ash and smoke.

A live feed from the volcano showed several visitors inside the crater before the stream went dark.

According to Ms Ardern, there were two groups on the island at the time, “those who were able to be evacuated and those who were close to the eruption”.

Some survivors were rescued by boat in the immediate aftermath of the explosion, but police said it was too dangerous to mount a rescue operation.

But later private helicopter rescue missions picked up several people from the island.

Speaking on Tuesday morning, Prime Minister Ardern paid tribute to helicopter crews who had flown to the island on Monday to bring people out despite the dangers.

“I want to acknowledge the courageous decision made by first responders and those pilots who in their immediate rescue efforts made an incredibly brave decision under extraordinarily dangerous circumstances in an attempt to get people out,” she said.

Since then, emergency services have been unable to search the area because of dangerous conditions, with plumes of smoke and ash continuing to rise above the volcano on Tuesday.