Keita Saito, a 39-year-old kanbu (leader) of the Takinogawa family, part of the Sumiyoshi-kai crime syndicate — the second-largest yakuza group in Japan — was arrested in late April.

He is suspected of involvement in a 2022 robbery which saw the theft of goods worth 252,000 yen (around €1,500 or £1,300) from an office in Ogano, near Tokyo.

Tokyo police said the goods included 25 Pokémon cards, though did not say how much they were worth, English-language Japanese news site SoraNews24 reports.

The involvement of fearsome Japanese gangsters in the theft of simple Pokémon cards has attracted widespread derision on Japanese social media.