NAGANO - Rescue teams comprising personnel from the Nagano and Gifu prefectural police, the Ground Self-Defence Force and fire departments resumed search-and-rescue operations on Mt. Ontake early Tuesday, but were forced to suspend efforts only 90 minutes later because of signs volcanic activity could intensify.
The GSDF initially planned to mobilize several CH-47 Chinook helicopters to accelerate efforts to reach climbers said to be in cardiopulmonary arrest, a standard description of victims whose apparent deaths have not been confirmed, who remain near the summit of the 3,067-meter-high volcano.
But the GSDF decided not to deploy the large transport helicopters after rescue operations were suspended.
According to the Nagano prefectural government's disaster countermeasure headquarters, 851 rescue workers were involved in Nagano-side operations Tuesday.
CH-47 helicopters, with a capacity of 55 people each, were to be mobilized to transport 180 rescue workers to near the summit.
But the Japan Meteorological Agency observed volcanic tremors after 6:12 a.m. Tuesday, which measured around the same level as the one that occurred immediately after the eruption Saturday.
Rescue operations were then suspended at 7:05 a.m with midsize helicopters remaining on standby as of 1 p.m.
The Nagano prefectural government subsequently announced at 2:20 p.m. that search-and-rescue efforts would be called off at least until the following day.
Volcanic gas is also hampering rescue efforts. The agency predicts westerly or west-northwesterly winds ranging from 18 kph to 50 kph at an altitude of 3,000 meters near the summit of Mt. Ontake.
A large amount of gas expelled from around the crater may cover areas where rescue teams would operate, the agency said.
Since rescue operations were called off, the exact number of climbers still on the mountain remains unknown.
According to the Nagano and Gifu prefectural governments, 12 people were identified and confirmed dead as of 8 a.m. Tuesday. Twenty-four people in cardiopulmonary arrest remain on the mountain.