A volcano in central Japan erupted in spectacular fashion on Saturday, catching mountain climbers by surprise and injuring at least 40 people who were stranded in areas that rescue workers have been unable to reach. Another seven people were missing. With a sound likened to thunder, Mt. Ontake spewed large white plumes high into the sky, sending people fleeing and covering surrounding areas in ash. Sohei Hanamura, a crisis management official in Nagano prefecture, the injured were in mountain lodges, because they were unable to descend 3,067-meter Mount Ontake on their own. Thirty-two people had serious injuries, including at least seven who lost consciousness. Japan’s meteorological agency raised the alert level for Mount Ontake to 3 on a scale of 1 to 5. It warned people to stay away from the mountain, saying ash and other debris could fall up to 4 kilometers away.