Scuffles have broken out between Turks and Kurds in the Japanese capital as hundreds of Turkish citizens had gathered at their embassy for early voting in Turkey's elections.
Several people were injured in Sunday's incident that was broken up by Japanese police.
A Turkish voter told Japan's Jiji Press that the clash began after Kurds tried to display the flag of a pro-Kurdish party.
A Kurdish man whose shirt had been torn off told the media outlet: "I was attacked by Turks all of a sudden while I was in a car with my friends."
Another Kurdish man, 40-year-old Ali Ayyildiz, said those supporting the Turkish government were the cause of the conflict.
He said people close to the Turkish government "came early in the morning and taunted the Kurdish youths here saying: 'The Kurds are in parliament, but we have no need of parliament' and started a brawl. They turned it into a big fight in the hope that the elections in Tokyo would be cancelled," he said.
About 3,600 Turkish nationals reside in Japan, according to the country's foreign ministry.
The election, to be held in Turkey on November 1, comes at a time of escalating violence in the country's mainly Kurdish southeast, despite a 2013 ceasefire in a three-decade insurgency that has claimed tens of thousands of lives.
Turkish President Recep Tayyip Erdogan called the poll after his ruling Justice and Development Party (AKP) lost its governing majority for the first time in June 7 elections, forcing it into coalition talks that ended in failure.
The AKP won three decisive general election victories in 2002, 2007 and 2011 but was stripped of its overall majority in June after losing support to a pro-Kurdish party.
The result damaged Erdogan's hopes of creating a powerful US-style presidency with full executive powers.
The pro-Kurdish Peoples' Democratic Party (HDP) and its leader, Selahattin Demirtas, have accused Erdogan and his party of whipping up nationalist sentiment ahead of the election while enforcing a security crackdown in the mainly Kurdish southeast.