Efforts to clean up the destroyed remnants of a residential neighbourhood in Hiroshima were underway on Wednesday after heavy rains wrought havoc on the area and several others around western Japan.

A landslide in the Kuchitaminami area on the outskirts of Hiroshima city killed three people, and swept away homes in a tangle of mud and broken trees.

Heavy machinery could be seen trying to remove the rubble, while families had to cross precarious damaged road and flood streams.

Japan's state broadcaster NHK reported on Wednesday morning that the national death toll from the heavy rains had risen to 159, with 57 people still unaccounted for.

Prime Minister Shinzo Abe is scheduled to visit one of the affected areas to inspect the damage later in the day.