At least four people were killed and dozens injured after Typhoon Nabi lashed southern Japan and South Korea Tuesday.

At least 16 others were reported missing as waves slammed into coastal barriers and storm surges flooded seaside towns.

More than 100,000 people were ordered to evacuate ahead of the typhoon, which brought winds of 126km/h and up to 1.3m of rain as it pounded the coastal city of Isahaya on Japan's southernmost main island of Kyushu.

Heavy rain and wind also tore through the neighbouring main island of Shikoku.

Transport in the area has been severely affected after the typhoon triggered landslides and floods.

The four dead were caught in two landslides in Kagoshima and Miyazaki prefectures on Kyushu island.

Japan's government sent 70 members of its Self-Defence Force to strengthen barriers, cope with flooding and help evacuees.

The typhoon grounded hundreds of flights, blocked trains and ferry services and closed down highways, stranding tens of thousands of travellers.

"The wind and rain was so strong earlier this morning, I could hardly walk -- I couldn't leave the building," Mitoshi Shiroi told The Associated Press from his flooded grocery store in Tarumizu, Kagoshima.

"The water just keeps on coming in from under the door. And my products will be ruined without electricity," he added.

The typhoon also forced Prime Minister Junichiro Koizumi to cut short a two-day campaign trip to western Japan ahead of national elections on Sept. 11.

He was to return to Tokyo on Tuesday evening to avoid the storm, an official from the Liberal Democratic Party said on condition of anonymity, citing party policy.

The eye of the typhoon made landfall on the island of Kyushu, where about 10% of Japan's population lives, at 1400 local time.

It then moved slowly north before heading towards the Sea of Japan. It was expected to continue north towards South Korea on Wednesday.

Ferry services from Fukuoka to South Korea, and from elsewhere in Kyushu to western Japan, were cancelled. About 20,000 air passengers had their flights cancelled.

Kyushu's electricity system was also affected, with 270,000 houses suffering power cuts, Kyushu Electric Power Co. spokesman Tetsuo Yano said.

Nabi, meaning butterfly in Korean, came in the wake of Typhoon Talim, which battered Taiwan and China last week. The reported death toll in China has risen to at least 84.

Typhoon Nabi will be the first typhoon to hit South Korea this year. One or two typhoons usually affect South Korea at this time of year.