Parts of western Japan were deluged by rain early Sunday, triggering mudslides and floods that left at least two people missing in Shimane and Yamaguchi prefectures.

The storm prompted the weather agency to warn that "some areas are seeing unprecedentedly heavy rains" and to tell the public to be on the lookout for floods and mudslides.

The warning issued for the two prefectures in the Chugoku region, where heavy rain was expected until evening, is equivalent to the "special warning" designation the Meteorological Agency intends to introduce starting Aug. 30, agency officials said. The special warning means that the risk of a "serious disaster" is high.