TOKYO, March 27 (Xinhua) -- Six students hit by an avalanche on a ski slope in Japan's Tochigi Prefecture were found not to be breathing Monday morning, and others remained unaccounted for, local rescue officials said.

They said the avalanche occurred on a ski slope in the town of Nasu, Tochigi Prefecture.

About 50 senior high school students and a dozen teachers were believed to be on the slope when the avalanche occurred, local media said.

The avalanche struck the Nasu onsen Family Ski Resort in the morning, while students were taking part in a springtime climbing event.

Emergency calls were received following the avalanche at 9:20 a.m. local time by emergency dispatchers.

The students and teachers were from several different schools and were taking part in a springtime climbing event when the accident happened, said the reports.

A teacher and two other students were also hurt in the avalanche, local reports also said.

The springtime climbing event began on Saturday and was supposed to finish at noon on Monday, a representative of one of the schools involved said.

The Tochigi Fire and Disaster Prevention Division said that rescue measures are currently ongoing.

The prefectural Board of Education in the area said that 66 people, including 11 faculty members, joined the climbing workshop from seven high schools in the prefecture and were all concurrently receiving workshops to do with mountaineering on three different slopes when the disaster happened.