FILE PHOTO: Flowers are seen at a memorial at the harbour in Whakatane, following the White Island volcano eruption in New Zealand, December 11, 2019. REUTERS/Jorge Silva/File Photo

WELLINGTON (Reuters) - A police helicopter looking for two bodies still missing after a New Zealand volcano eruption last week was forced to return due to bad weather, police said on Tuesday.

The official death toll from the surprise eruption on White Island, also known by its Māori name of Whakaari, stands at 16. Six bodies were retrieved from the island on Friday.

Those still missing, presumed dead, are Winona Langford, a 17-year old Australian, and Hayden Marshall-Inman, a 40-year old New Zealand tour guide. Their bodies are believed to be in the waters around the island.

“I know that every effort is being made...weather is currently conspiring against them and that is a very dangerous environment in which they are working,” Australian Foreign Minister Marise Payne told reporters in Auckland during a visit to meet with officials following the eruption.

The dead include 11 Australian citizens, three Australian permanent residents and one New Zealander. One other person, whose name has not been released, died after being transferred to an Australian hospital.

There has been growing criticism that people were allowed on the island, a popular destination for day-trippers, given the risks of an active volcano. That has led to speculation the tragedy could lead to major changes for New Zealand’s thrillseeker tourism industry.

New Zealand Prime Minister Jacinda Ardern said on Monday that official inquiries by coroners and work safety regulators into the eruption could take up to a year, and will carry potential criminal penalties of up to five years in jail.

She is seeking advice from officials on whether a broader investigation is needed.