TOKYO - Japanese authorities on Thursday called off the search for seven hikers still missing on a volcano that unexpectedly erupted last month, as wintry conditions made the search operation increasingly difficult.
Troops, firefighters and police have been scouring Mount Ontake in central Japan for the missing climbers since the volcano erupted without warning on September 27, killing at least 56, in Japan's deadliest eruption for almost 90 years.
"We have decided to call off the operation for the rest of this year," said an official of the crisis-management office of Nagano prefecture, where the volcano sits.
"Snowfalls and freezing on the slope ahead of this year's full-fledged winter were already adding to the tough conditions up there," the official said.
"We won't carry out the large-scale operation, but we may begin a small-sized one next year when spring comes," he added.
Rescue workers have described the slopes of the volcano as being smothered in thick, sticky ash, up to half a metre (20 inches) deep, with some of the dead found half-buried, leading to fears others may be entombed.
Rescuers were using hand-held metal detectors and sticking poles into the ground in a bid to find victims possibly buried under the ash.
The rescue work was earlier stalled by heavy rain triggered by typhoons.
Mount Ontake was packed with walkers out to witness the region's spectacular autumn colours when it burst angrily to life.
The volcano continues to belch steam and poisonous fumes, making a section near the crater inaccessible.