Heavy snow caused a power outage along parts of the Joetsu Shinkansen Line for about six hours on Sunday morning, leaving some 300 passengers trapped in a bullet train for 2½ hours near the mountainous southern border of Niigata Prefecture.

East Japan Railway Co. (JR East) said the outage was likely caused by excess snow on the roof that caused electricity, which is normally transmitted to cars via the pantograph, a current collector, to be diverted. There were no reports of injuries or sickness, JR East said.

The bullet train for the Max Toki 300 service left Niigata bound for Tokyo but was halted between Echigo-Yuzawa and Urasa stations by the power failure, which occurred at 6:42 a.m., JR East said.

The blackout left the cars without light and heat, but the passengers were taken back to Urasa Station aboard a different train about 2½ hours later, it said.

The outage forced the railway to suspend high-speed rail services between Echigo-Yuzawa and Niigata stations until the early afternoon.