Two people were found dead early Tuesday in an overturned fishing boat off Yamaguchi Prefecture, and another fishing boat with three people aboard was missing and possibly capsized off Hokkaido, the Japan Coast Guard said.
The fatalities are believed to be Kazumi Kashima, 53, and his brother, Yoshio, 51.
Their 4-ton boat, the Kazuyoshi Maru No. 3, was found some 20 km off Hofu, Yamaguchi Prefecture.
Damage to the vessel indicates it may have been involved in a collision, and the coast guard is investigating the case as a hit-and-run.
In Hokkaido, contact was lost with the Riko Maru No. 58 at around 3 a.m. while the vessel was fishing for squid off Wakkanai.
A coast guard aircraft observed an overturned boat about 5 km northeast of Noshappu Cape.
Toshimitsu Osuga, 58, Yoshio Sato, 53, and Kenichi Kobayashi, 58, were on board the 19-ton Riko Maru, according to the local fisheries association.
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