The Nagano District Court on Thursday found the president of a bus operator and a former operations manager guilty and handed them prison terms on charges stemming from a crash in 2016 that killed 15 people in a mountain resort town in central Japan.

The court gave Misaku Takahashi, president of the Tokyo-based company ESP, a three-year prison sentence and Tsuyoshi Arai, an operations manager at the time of the crash, four years for professional negligence that resulted in death and injury over the accident in Karuizawa, Nagano Prefecture.

Takahashi, 61, and Arai, 54, pleaded not guilty. Prosecutors had demanded five-year prison terms for both men.

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

The trial focused on whether Takahashi and Arai were responsible for the accident even if they were not present at the crash site.

According to the indictment, Hiroshi Tsuchiya, who was driving at the time of the accident, had little experience piloting large buses like the one involved in the crash.

Takahashi had been informed of Tsuchiya's inexperience but failed to instruct Arai to have the driver trained sufficiently, the indictment said.

The prosecutors said during the trial that the company could have foreseen the accident given the inexperience of Tsuchiya, 65, but still allowed him to work despite him previously expressing concern about driving a vehicle of that size.

The defense counsel said that Tsuchiya did not apply the brake as the bus was going downhill, arguing it was difficult to predict that any certified driver would fail to take such a basic action.