The Nagano District Court on Monday found a mountain guide guilty of professional negligence resulting in death and sentenced him to three years in prison, suspended for five years, after four climbers in his care died in the Northern Alps in 2006.

According to prosecutors' closing arguments, the four climbers froze to death on Oct. 7, 2006, amid snow and high winds on a route between a hot springs resort in Kurobe, Toyama Prefecture, and a lodge on 2,932-meter Mount Shirouma.

Prosecutors said guide Kazuhiro Tagami, 57, should have recognized the risk of developing hypothermia in the severe weather, given it was raining from the time the group began its climb and the route followed a windswept ridge.