Three men were injured on Wednesday in a stabbing incident and taken to hospital after a woman wielded a knife on a train at Akihabara Station in Tokyo.
The police received an emergency call just before 11:00 pm local time (1400 GMT) saying the woman had inflicted injuries with a knife on the Yamanote loop line, one of the busiest transport routes in the city.
The woman was taken into custody while the condition of the three injured men was unknown, a Tokyo Metropolitan Police Department spokesperson said.
Kyodo news agency reported that none of the victims had suffered life-threatening injuries.
Public broadcaster NHK initially reported that four people had been stabbed.
East Japan Railway Company said the Yamanote loop line was briefly suspended due to "trouble on the train".
Akihabara, traditionally home to retailers of electronics and gadgets, is a major tourism hotspot in Tokyo and has become synonymous with video games, comic books and outlandish fashion.
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