The Japan Coast Guard and local authorities continued searching Sunday for five members of the Ground Self-Defense Force who went missing Saturday morning while fishing on Lake Saroma in northeastern Hokkaido.

The five were thrown into the water along with five other GSDF personnel when the pleasure fishing boat carrying them capsized.

About 620 people including divers have been mobilized for the search and have deployed devices using sonic waves to look for the missing five, coast guard officials said.

The search party, which worked through Saturday night, has found coolers and fishing rods believed to have come from the fishing boat.

Five of the 10 GSDF personnel, from a base in Asahikawa, Hokkaido, were pulled from the water after the boat capsized. Two of them died after being taken to hospital.

The 8.6-meter Hayabusa capsized between Lake Saroma, Japan's third-largest lake, and the Sea of Okhotsk due to high waves, according to the officials.

Eight of the 10, including the missing five and the two who subsequently died, were not wearing life jackets, they said.