The person, who was not identified, died Sunday night at a hospital in the city of Auckland, New Zealand Police Deputy Commissioner John Tims said in a statement.
Two people — a 40-year-old New Zealand man and an Australian teen — were still missing after the Dec. 9 eruption on White Island, Tims said last week.
He added that experts believed their bodies had likely washed out to sea.
“We have always had an expectation of ourselves and others that all bodies would be recovered, so it’s both disappointing and frustrating to be in this position,” he said.
Forty-seven people were visiting the privately owned volcanic island, a popular tourist destination off the east coast of New Zealand’s North Island, when the eruption occurred.
Several Americans were among the dead and injured. A newlywed couple on their honeymoon from Richmond, Virginia, were badly burned, relatives said. Two teenage brothers visiting from Australia, where they had moved with their parents, were among those who died, according to authorities.
Tim Stelloh is a reporter for NBC News, based in California.