A shinkansen bullet train conductor in Japan.
Getty/Buddhika Weerasinghe

A Japanese bullet train driver is facing punishment after leaving the cockpit to go to the toilet while traveling at 150km/hr (93mph).

The shinkansen train was carrying 160 passengers between Tokyo and Osaka on Sunday, May 16 when the driver left the helm due to a stomach ache, the BBC reported.

The unnamed 36-year-old left a conductor - who was not licensed to drive - in charge of the Hikari 633 train for three minutes, but they did not touch the controls.

It was around 08:00 at the time, and the train was between Atami station and Mishima station in Shizuoka Prefecture, a spokesperson for Central Japan Railway Co. (JR Central) told CNN Travel.

Shinkansen bullet trains are known for their punctuality, but when the train in question arrived at its destination one minute late, an investigation was launched, according to the Guardian.

Both the driver and the conductor are now facing disciplinary action, and the train operator has apologised for the "extremely inappropriate" behaviour.

The driver has also apologised, saying he didn't go to the bathroom at a station because he didn't want to cause a delay.

The shinkansen bullet train network is one of Japan's most prominent icons, Insider's Rachel Premack and Mary Meisenzahl reported, and its punctuality is a point of pride. The top operating speed of a bullet train is 321km/hr (200 mph).

In 2018, the Japanese national railway issued an apology after a train left the platform 25 seconds earlier than its scheduled departure time.

The "great inconvenience" was "truly inexcusable," it said in a statement, as Insider's Lucy Yang reported at the time.

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