Concerns over new tremors at Japan volcano Increased seismic activity is raising concerns about the possibility of another eruption at a Japanese volcano where 36 people were killed, hampering efforts to recover at least 24 bodies still near the summit Approximate area of eruptionAt least 250 hikers believed to be on mountain when it erupted unexpectedly on September 27 Gifu Prefecture Summit 3,067m Mountain lodge Centre of recovery operation Nagano Prefecture Volcano craterLast major eruption occurred in 1979 MOUNT ONTAKE 1,000m 3,300ft Detail map Mount Ontake Nagano Prefecture Tokyo Gifu Prefecture 100km 60 miles JAPAN Some bodies found in lodge near summit, others buried in ash up to 50cm deep. Experts say victims probably died from suffocating ash, falling rocks and toxic gases Source: Wire agencies Pictures: Associated Press, Google Earth