New Zealand military specialists wearing protective suits have recovered the bodies of six victims of a volcanic eruption on Monday.

The experts – six men and two women wearing hooded protective gear and using breathing apparatus – landed on White Island by helicopter on Friday and found six of the eight bodies thought to be there.

Prime minister Jacinda Ardern said at a news conference: “We know that reunification won’t ease that sense of loss or grief, because I don’t think anything can. But we felt an enormous duty of care as New Zealanders to make sure that we brought their family members back.”

The families cheered and expressed joy and relief on being told of the successful recovery, Police Deputy Commissioner Wally Haumaha said. “They’ve got their loved ones coming home.”

The bodies were airlifted to a nearby ship, where the risky operation was being monitored.

Toxic volcanic gases are still venting from the crater, and scientists have said another eruption is possible.

The bodies were to be taken to Auckland for identification. They are thought to be Australians, who were most of the visitors to the island on Monday when the volcano erupted.

Another recovery operation was planned for the last two bodies, thought to be New Zealanders – a tour guide and a boat captain who had taken tourists to the island.

Police Commissioner Mike Bush said police divers were deployed to search the sea around the island and aerial surveillance would be used to try to locate them.

“We do believe that at least one of them is in the water and the other one we are unsure,” but the body may be in the sea as well, Bush said at a news briefing.

“We will continue to search for these people,” he added.

Conditions were good for the recovery operation and the volcano was “quiet” as the team worked, Police Deputy Commissioner Mike Clement said.

Scientists have warned that White Island, which is the exposed tip of a mostly undersea volcano, is “highly volatile” and has been venting steam and mud regularly.

The eruption on Monday happened as 47 tourists and their guides were exploring the island. Many of the survivors were severely burned.

Australia has transported several of its patients to burn units back home, and specialist medical teams were heading to New Zealand from Australia, Britain and the United States. Skin banks were also sending tissue to New Zealand hospitals to use for grafts.

Authorities say 24 Australians, nine Americans, five New Zealanders, four Germans, two Britons, two Chinese and a Malaysian were on the island at the time. Many were from a Royal Caribbean cruise ship that had left Sydney two days earlier.