The search for Kyushu's missing continued Sunday as the Meteorological Agency forecasted more heavy rain for some of the areas wrecked by the island's deadly flooding and mudslides last week.

Around 30 people are still unaccounted for in Fukuoka and Oita prefectures, which have been inundated by torrential rain since Wednesday that has so far claimed 18 lives.

About 250 people were still stranded in the two prefectures, with some 1,700 stuck in evacuation shelters, according to local authorities.

In the meantime, the bodies of five people recovered Saturday from the Ariake Sea remain unidentified. They are believed to be flood victims who were washed away in the upper reaches of the Chikugo River.

The Meteorological Agency said parts of Kyushu may see more heavy rain Sunday because a seasonal rain front is lingering near the region.

Officials in Asakura in Fukuoka Prefecture, which took some of the heaviest damage from the storm, advised more than 300 residents living near a mountain on Sunday afternoon to evacuate because of the high landslide risk.

In Tokyo, the government pledged to do its utmost to help the damaged municipalities recover, possibly via disaster subsidies.

Chief Cabinet Secretary Yoshihide Suga, the top government spokesman, told reporters Saturday that the government will help Kyushu Railway Co. rebuild parts of the Kyudai Line, including a bridge that was washed away in the village of Hita in Oita.

"The railway is an important piece of infrastructure for the region. We'll lend as much support as possible," Suga said.