Firefighters carry elderly people on their back to rescue from an isolated area in MinamiFurano, Hokkaido on Aug 31, 2016. Powerful Typhoon Lionrock hit Tohoku, Hokkaido regions, bringing heavy rain and mudslides. [Photo/IC]

TOKYO - Nine people were killed when floods inundated an old people's home in Japan, police said on Wednesday, taking the death toll from a typhoon battering northern parts of the country to at least 11.

Police found nine bodies on Wednesday in the nursing home in the town of Iwaizumi, in Iwate Prefecture in the north of Japan's main island of Honshu, but it was not clear when their home was flooded.

It was also not clear why people there had not been taken to safety before the storm struck. The nursing home is located near a river and was partially buried in mud and debris when the river overflowed its banks.

"The area is in a state of chaos. We are not sure what preparations the facility had taken," said a prefectural government official who asked not to be identified because he was not authorized to speak to the media.

The town issued evacuation preparation information on Tuesday morning, which is to inform elderly or disabled people who take time to evacuate. That, however, was not as strong as an evacuation warning, according to another prefecture official.