Work has continued overnight to respond to the eruption on White Island.

Enquiries with tour operators indicate that 47 people were on White Island at the time of the eruption.

Police can now advise that in addition to the five people confirmed deceased, eight people remain unaccounted for following the eruption.

Casualties have been moved to hospitals around the country for specialist care.

Thirty-one patients are currently being treated at seven hospitals.

Three patients have been treated and discharged from Whakatane Hospital.

Rescue helicopters, the Police Eagle helicopter, and NZDF aircraft have undertaken a number of aerial reconnaissance flights over the island since the eruption, and further reconnaissance flights will be undertaken this morning, says a police spokesperson.

Both New Zealanders and overseas tourists are involved, including 37 passengers and one crew member from the Ovation of the Seas cruise ship.

"The family and loved ones of those involved are front of mind for police.

"Support is being put in place and Police are working to provide them with information as it becomes available."

Anyone who wishes to submit information regarding family or loved ones who might have been visiting White Island during the eruption should call Police on 105.

People overseas can call +64 9105 105, or use the online form on the Police website here.

At the request of NZ Police, New Zealand Red Cross has activated the Family Links website for people wanting to register themselves as safe or register an inquiry about a loved one.

"If you are worried about a family member or loved one following the White Island eruption, first contact them as you normally would."

If you cannot make contact, you can register them through this website: https://familylinks.icrc.org/new-zealand/en/Pages/Home.aspx