Typhoon Meari continued to lash Japan with heavy rain, leaving 12 people dead and another 12 missing, weather officials and police said.

The season's 21st typhoon in the Pacific region, and the eighth to directly hit Japan, landed on Kyushu early on Wednesday.

A 47-year-old woman and her 18-year-old daughter were found dead early Thursday after a mudslide washed away their home in Niihama City, Ehime prefecture, some 700 kilometres (430 miles) southwest of Tokyo.

Two neighbours who tried to rescue them were also killed, according to local police.

Four others have also died in Ehime since Wednesday while another three were killed in the central Japan prefecture of Mie.

A 70-year-old man was found dead Wednesday in a water-purification tank in the premises of his food company factory in Kagoshima City on Japan's southern main island of Kyushu after he left home to check the factory facilities.

Eight people are missing in Mie and another four in Ehime. More than 40 people were injured in southern and western Japan.

The storm weakened slightly to pack wind speeds of 82.8 kilometers (50 miles) per hour Thursday morning, but the Meteorological Agency warned it can still bring about heavy rainfalls that can trigger mudslides and flooding.

The typhoon was near Mizusawa City, 400 kilometres (250 miles) north of Tokyo, early Thursday and moving northeast at accelerated speed of 60 kilometres per hour.

It is expected to dissipate into a temperate depression later Thursday.

Source: CD/Agencies