NAGANO, Japan, Sept. 27 (UPI) -- At least 40 hikers were injured in Japan Saturday when volcano Mount Ontake erupted. The eruption sent a dark plume of smoke into the air, ejecting rubble and covering the surrounding area in a thick layer of white ash. Witnesses reported a thunder-like boom as the volcano exploded.
Japanese news station NHK reports that some hikers remain missing and several have been reported unconscious. Sources suggests fatalities are likely to be reported in the coming hours. Several dozen momentarily took shelter in a trailside hut.
"We expect a lot of injured people so we are now getting ready for their arrival," a local hospital official told NHK.
"I escaped with my bare life," one of the hikers told NHK in TV news segment. "Immediately after I watched the eruption, I rushed away but I was soon covered with ash."
There were apparently several hundred people on the mountainside at the time of eruption. Many who weren't stranded made their way back down as the cloud of ash grew behind them. Several hikers documented their descent and posted their photos to social media sites like Facebook and Twitter.
御嶽が噴火した やばい、遭難した pic.twitter.com/mobJ2mqhNh— MM (@mori____mori) September 27, 2014
Japanese Prime Minister Shinzo Abe ordered the country's defense forces to initiate a rescue operation for any hikers that may be still trapped on the volcano.
Rising more than 10,062 feet, Mount Ontake is the second highest volcano in Japan and a popular hiking destination, especially in the fall when its elevation offers expansive views of the trees and their turning leaves below.
The volcano lies in the central Chubu region of Japan's main island, about 155 miles west of Tokyo. It last erupted in 2007.