Updated

Russian officials say that four Coast Guard officers died and six others are missing after their boat overturned in rough seas near Japan.

The Investigative Committee, the nation's main investigative agency, said the incident happened Saturday when a group of Coast Guard officers went to inspect a fishing vessel detained in the Yuzhno-Kurilskaya Bay off Kunashir Island on allegations of poaching in Russia's territorial waters.

Officials say the Coast Guard boat overturned in stormy weather. Rescuers have found the bodies of four victims, and a search was underway for the missing.

Kunashir, just off the northeastern tip of Japan's Hokkaido Island, is one of the four islands controlled by Russia since WW II but claimed by Japan.