Kazuki Takahashi, the creator of the popular "Yu-Gi-Oh!" manga series, was found dead in the ocean off the coast of southern Japan while on an apparent snorkeling trip, according to coast guard officials. He was 60.

Takahashi was wearing snorkeling gear and flippers when he was found Wednesday morning around 300 meters off the coast of Nago in Okinawa Prefecture by a local tourism worker who then alerted the authorities, the officials said Thursday.

Photo taken in July 2022 shows a copy of the popular "Yu-Gi-Oh!" manga series and related game cards. (Kyodo)

Police are investigating the cause of his death, the officials said, adding that he may had been traveling alone.

A car rental firm consulted police Wednesday when they were unable to make contact with Takahashi after renting him a vehicle. His car was found parked near a beach in Onna, some 12 kilometers from where his body was discovered.

Born in Tokyo, Takahashi, whose real name was Kazuo Takahashi, debuted as a manga artist in the 1980s. His "Yu-Gi-Oh!" series featured a high school student who becomes possessed with an ancient spirit and settles disputes by playing a card game involving magical creatures.

The work was serialized in Shueisha Inc.'s Weekly Shonen Jump magazine from 1996 to 2004, with total circulation including digital publication reaching over 40 million.

The official card game based on the series was released in more than 70 countries and regions, and was certified as the "best-selling trading card game in the world" by Guinness World Records.

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