New Zealand Deputy Police Commissioner John Tims said Tuesday local police have begun a criminal probe after Monday’s eruption of the White Island volcano. An investigation by health and safety regulators will be the basis for any ongoing police action.

Five deaths were confirmed after the eruption and another eight people are believed to have died, with their bodies remaining on the ash-strewn island for now.

As Breitbart News reported, police believe there were 47 visitors on the island at the time of the tragedy. They say 24 were Australian, nine were American and five were New Zealanders. Others were from Germany, Britain, China and Malaysia. Many were passengers aboard the Royal Caribbean cruise ship Ovation of the Seas.

Many people were left questioning why tourists were still allowed to visit the island after seismic monitoring experts raised the volcano’s alert level last month.

“These questions must be asked and they must be answered,” Prime Minister Jacinda Ardern said in Parliament.

My god, White Island volcano in New Zealand erupted today for first time since 2001. My family and I had gotten off it 20 minutes before, were waiting at our boat about to leave when we saw it. Boat ride home tending to people our boat rescued was indescribable. #whiteisland pic.twitter.com/QJwWi12Tvt — Michael Schade (@sch) December 9, 2019

White Island, also known by the indigenous Maori name Whakaari, is the tip of an undersea volcano about 50 kilometers (30 kilometers) off New Zealand’s main North Island.

New Zealand’s GeoNet seismic monitoring agency had raised the volcano’s alert level on Nov. 18 from 1 to 2 on a scale where 5 represents a major eruption, noting an increase in sulfur dioxide gas, which originates from magma.

It also said volcanic tremors had increased from weak to moderate strength. It raised the alert level to 4 for a time after Monday’s eruption but lowered it to 3 as the activity subsided.

The volcano has a long — and perhaps predictable — history of unpredictable activity.

In 1914 ten people were killed after a landslide on the crater floor. It erupted almost continuously between 1976 and 2000.

“Hindsight is always 20/20, but any visit to an active volcano, or volcanic field bears a certain amount of risk,” said tourism professor Michael Lueck of the Auckland University of Technology.

“Usually it is managed by governmental bodies generally, and the tourism industry in particular.”

AFP contributed to this story