In the early hours of Thursday, Tokyo Metro Co. discovered one of its trains had been vandalized overnight with graffiti while parked near Nakano Station, the subway operator said.

The incident was the third in the past seven days where Tokyo Metro subway trains had been vandalized, according to the firm.

The graffiti was discovered by a train conductor performing regular checks in preparation for the train's first service of the day, at 5:08 a.m.