A New Zealand tour company has been found guilty of not "minimising risk" to 22 people who died in the 2019 White Island volcano disaster.
Judge Evangelos Thomas criticised what he said were "astonishing failures" by Whakaari Management Limited (WML) - which licenses tours to the island.
The case is the largest action of its kind brought by New Zealand's regulator, Worksafe NZ.
The company faces up to NZ$1.5m ($928,000; £724,000) in fines.
The December 2019 eruption killed 22 - almost half of the people who were on the island at the time. Most were tourists, including 17 from Australia and three from the US.
Another 25 people were injured, with many suffering extensive burns.
The volcano, known by its Māori name of Whakaari, had been showing signs of heightened unrest for weeks before the fatal eruption.
It is New Zealand's most active volcano and had been erupting in some form since 2011.
Thirteen parties were charged over the disaster. WML was the last to receive a verdict after six had pleaded guilty, while six more had their charges dismissed.
Sentences will be passed in February.
James, Andrew and Peter Buttle, three brothers who own the company, inherited the volcano and licenced other businesses to run tours.
They had also been on trial over alleged breaches of New Zealand's workplace health and safety legislation as individuals, but had those charges dismissed last month.
A lawyer for WML argued that it was merely a landowner without active control of tours to the island and how they were conducted.
But the judge said it "managed and controlled" the active volcano and failed in its duty to minimise the risk there.
This included a failure to conduct proper risk assessments and to adequately engage with the necessary experts.
"It should have been no surprise that Whakaari could erupt at any time, and without warning, at the risk of death and serious injury," said Judge Thomas.
He dismissed a second charge against the company relating to the safety of its workers.
The disaster prompted the most extensive and complex investigation ever undertaken by WorkSafe NZ, which was also criticised for failing to monitor activities on the island between 2014 and 2019.
Tourism activities on to White Island have not resumed since the eruption.
Some of the tourists who bought their tour ticket to Whakaari through Royal Caribbean Cruises have already reached settlements after suing the Florida-based company in the US.