The first deaths were confirmed Sunday among more than 30 hikers feared killed near the peak of a Japanese volcano that erupted without warning, spewing ash, rocks and steam. Rescue workers battling rocketing levels of sulphurous gas found 31 people in "cardiac arrest" near the summit of 3,067-metre (10,121-foot) Mount Ontake, which erupted around noon on Saturday, police and local officials said.
The term is usually applied before doctors can certify death. Four of those found were brought down the volcano on Sunday where they were confirmed dead, broadcaster NHK reported.
"According to the police, four people out of the 31 people who had been found in cardiac arrest near the peak were confirmed dead. All of them were men," a station anchorman told viewers.
The news appeared to confirm fears that there was little hope for those still on the volcano.
Rescue efforts were called off mid-afternoon Sunday because the environment was becoming too dangerous for emergency workers, an official at the Nagano prefectural government told AFP. "The rescue team suspended their operation because of the increasing concentration of sulphurous gas in the area," the official said.
Fire-fighters have separately confirmed a total 30 people with injuries, including one serious case, he said, adding that the number could still change.
Some 550 soldiers, police and fire-fighters took part in a major operation to reach those stranded on the volcano since it erupted into a sunny autumn sky during a busy weekend for tourists and hikers.