With the nation marking the fifth anniversary of the eruption of Mount Ontake that killed 58 people and left five others missing, a government survey shows about half of the municipalities near active volcanoes do not have evacuation plans in the event of an emergency.

Only 105 of the 190 cities, towns and villages in designated warning areas near Japan's 49 volcanoes had compiled evacuation plans as of late July under a law that was revised in 2015 following the country's deadliest postwar volcanic disaster, the Cabinet Office said recently.

The 3,067-meter-high Mount Ontake, which straddles Nagano and Gifu prefectures, suddenly erupted without warning in 2014. The law revision was aimed at improving preparedness for such a situation by obliging local governments near volcanoes to draw up evacuation plans based on hazard maps and disaster scenarios.