The death toll from floods in Japan in recent days has risen to seven, as rescuers searched for 15 people still missing.
Police on Sunday (local time) found the bodies of two men in rice paddies in Joso, the worst-hit city.
Earlier in the day they discovered the body of a 68-year-old man inside a submerged car in a flooded rice field in the town of Tochigi, north of Tokyo.
Parts of Joso, a community of 65,000 residents, were washed away on Thursday when a levee on the Kinugawa river gave way, flooding an area spanning 32 square kilometres after the worst rains in decades.
Toru Takasugi, mayor of the city about 60km outside Tokyo, apologised at a press conference for not ordering residents to evacuate before the river burst its banks, local media reported.
"We thought it might break its banks, but we couldn't predict where. We are deeply sorry for not handling the situation properly," he said.
Four days have passed since the flooding, but a total of 1800 rescuers including police, firefighters and military are still struggling to find 15 people still missing from Joso, public broadcaster NHK said.
The weather agency warned of the possibility of more heavy rain in the flood-hit area later in the evening.
Officials said more than 1650 people were still at evacuation centres in Joso on Sunday afternoon, with more than 4000 houses submerged and the water supply remained cut off.