Evacuation warnings after Typhoon Nanmadol makes landfall in Japan

Japan is currently in typhoon season and faces around 20 such storms a year, routinely seeing heavy rains that cause landslides or flash floods

Millions of people in Japan were under evacuation warnings on Monday as Typhoon Nanmadol brought strong winds and heavy rain to the southwest of the country after making landfall overnight.

The powerful system has weakened since arriving on land on Sunday evening around Kagoshima city in the southwestern region of Kyushu, but it has still uprooted trees, smashed windows and left rivers close to overflowing.

National broadcaster NHK said one person had been killed and 50 others injured as the storm passed through Kyushu. There was no immediate confirmation of the figures from authorities.

Prime Minister Fumio Kishida, who had been scheduled to leave Monday for the United Nations General Assembly, will delay his trip by a day to check on damage from the storm, his office confirmed.

Officials from the Japan Meteorological Agency warned that in Miyazaki prefecture, where some areas saw more rainfall in 24 hours than they normally receive in all of September, river levels were high.

"Even a tiny amount of additional rainfall could cause the water level to increase, so please remain vigilant about flooding and landslides," Yoshiyuki Toyoguchi from the land ministry told reporters.

Still, given the intensity of the storm, which came ashore packing gusts of up to 234 kilometres (145 miles) an hour, damage appeared relatively limited so far.