The former operations manager of a bus firm has appealed a court ruling that sentenced him to four years in prison for a crash in 2016 that killed 15 people in a mountain resort town in central Japan, court documents showed Friday.

Tsuyoshi Arai, 54, the operations manager of Tokyo-based bus firm ESP at the time of the crash, filed an appeal after the Nagano District Court on Thursday found him guilty of professional negligence resulting in deaths and injuries over the accident in Karuizawa, Nagano Prefecture.

The defendant had pleaded not guilty, saying he could not have foreseen the accident.

Photo taken June 8, 2023, shows the Nagano District Court. (Kyodo)

The court ruled that Arai had failed to provide necessary training or skills testing for the driver at the time of the accident, Hiroshi Tsuchiya.

In the early hours of Jan. 15, 2016, an ESP ski trip charter bus careened off a road in Karuizawa after hitting a guardrail. Tsuchiya and a second driver along with 13 university students aboard were killed while 26 others were injured.

The 65-year-old Tsuchiya had little experience piloting large buses and was unable to properly operate the gears or brakes as the bus went down a hill, according to the ruling.

In the trial, the district court also sentenced Misaku Takahashi, the 61-year-old president of ESP, to three years in prison.

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