A flash flood struck a high school hiking group at a wilderness gorge in New Zealand, sweeping six teenagers and a teacher to their deaths in a tragedy that shocked the country.
Five other students were plucked to safety from the torrent Tuesday in the Mangatepopo River in the Tongariro National Park on New Zealand's North Island.
"It is a tragedy which defies belief," school principal Murray Burton told reporters. Students clutched each other in tears as Burton read out a roll call of those who died during a special assembly Wednesday at the Elim Christian High School in Auckland, New Zealand's largest city.
Prime Minister Helen Clark expressed "profound sympathy and shock" and moved a condolence motion in Parliament.
"This is every family and school's worst nightmare," said Clark, a mountaineer and wilderness lover. "To have this happen when young people are out doing a healthy and normally very enjoyable activity, and it turns into a terrible tragedy."
The six students who died were all aged 16 and the teacher was 29.
Officials said there was no apparent warning to the group when the river rose to about four times its normal water level in the narrow gorge within half an hour.
The teenagers were part of a group of 40 students attending a weeklong course at the Sir Edmund Hillary Outdoor Pursuits Center in the small town of Turangi. The course involved navigating the gorge by swimming, clambering over rocks and hiking.
Burton said the hiking group was well equipped with wet suits, life jackets and harnesses and that the students were in the care of an experienced guide. Those swept away were in a group of 12 that had separated from the main party.
District Police Inspector Dave White said the students were doing a team-building exercise traversing the river when they were overcome by the rapidly rising water levels late on Tuesday.
"It's too early to say exactly what happened as the matter is under investigation," White said.
Another officer, Inspector Steve Mastrovich said it appeared heavy rainfall from a surprise storm had caused a sudden flood of water in the river "and they've just been caught in the wrong place at the wrong time."
New Zealand's spectacular and rugged wilderness is world famous, and many of the country's inhabitants pride themselves on their close connection to it. Mountaineering, hiking and sailing are common pursuits among the nation's 4.2 million people.
Grant Davidson, chief executive of the center that organized the trip, said the conditions appeared safe and there had been no warning of the heavy rain that quickly developed in the area.
"I am comfortable this was a normal activity we had with this age group in these sort of conditions," he told reporters. "Obviously if we had known or predicted about the pulse of water we would not have been there."
He said that in 25 years of operating in the region, he had never seen the river rise and fall as quickly as it did on Tuesday.
Clark praised the center's strong reputation for working with young people in New Zealand's wilderness.
Police and the adventure company said they would further investigate whether there had been any safety breaches.
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