The FSB announced the arrest on Tuesday, saying the journalist was preparing to leave Russia when he was detained in Yuzhno-Sakhalinsk, the main city on Sakhalin Island. A video released by Russia's TASS news agency, attributed to the FSB, shows masked officers handcuffing the suspect in a hotel room and later escorting him to an interrogation room. He was then seen boarding a plane accompanied by two FSB servicemen, before appearing in a cage in a Moscow court, which authorised his custody for nearly two months.
The arrest comes amid heightened tensions between Russia and Japan following President Vladimir Putin's visit in August to the Kuril Islands, a Moscow-controlled Pacific archipelago that Japan also claims. The Sakhalin region includes the four southernmost islands of the Kuril chain, which Japan calls the Northern Territories. Russia and Japan have never signed a formal World War II peace treaty, with the territorial dispute being the main obstacle.
Since its invasion of Ukraine in 2022, Russia has arrested several foreigners on espionage charges. A prominent case was the 2023 detention of Wall Street Journal reporter Evan Gershkovich, who was sentenced to 16 years and later freed in a prisoner swap in August 2024. The Japanese government has not yet confirmed Imai's detention, and official reactions from Tokyo are pending as the case develops.