'Dangerous' Typhoon Nanmadol slams into Japan

Typhoon Nanmadol made landfall in southwestern Japan, as authorities urged millions of people to take shelter from the powerful storm's high winds and torrential rain.

The storm officially made landfall as its eyewall arrived near Kagoshima city, the Japan Meteorological Agency (JMA) said.

It was packing gusts of up to 234 kilometres per hour and had already dumped up to 500 mm of rain in less than 24 hours on parts of southwestern Kyushu region.

At least 20,000 people were spending the night in shelters in Kyushu's Kagoshima and Miyazaki prefectures, where the JMA has issued a rare "special warning" -- an alert that is issued only when it forecasts conditions seen once in several decades.

National broadcaster NHK, which collates information from local authorities, said more than seven million people had been told to move to shelters or take refuge in sturdy buildings to ride out the storm.

The evacuation warnings are not mandatory, and authorities have at times struggled to convince people to move to shelters before extreme weather.

They sought to drive home their concerns about the weather system throughout the weekend.

"Please stay away from dangerous places, and please evacuate if you feel even the slightest hint of danger," Prime Minister Fumio Kishida tweeted after convening a government meeting on the storm.

Utility companies said nearly 200,000 homes across the region were without power.