Prime Minister Shinzo Abe warns of prolonged economic impact from typhoon, which swept across country at the weekend.

The death toll in the worst typhoon to hit Japan in decades has climbed to 74 as rescuers slogged through mud and debris in an increasingly grim search for the missing.

Thousands of homes remained without power or water on Tuesday, as some children returned to schools following a public holiday.

National broadcaster NHK said 74 people were known to have died after Typhoon Hagibis swept across central and eastern Japan. Some 15 people remain missing, while more than 200 were injured in the storm, whose name means “speed” in the Tagalog language.

About 138,000 households were without water while 24,000 had no electricity, well down on the hundreds of thousands who were initially left without power but a cause for concern in northern areas where temperatures are forecast to fall.

The highest toll was in Fukushima prefecture north of Tokyo, a largely agricultural area where the Abukuma River burst its banks in at least 14 places.

At least 25 people died in the area, including a mother and her child who were caught in floodwaters. Her other son, who was caught up in the flood with her, remains missing.

Typhoon-damaged cars on a mud-covered street in Hoyasu after Typhoon Hagibis swept through central and eastern Japan [Jae C. Hong/AP Photo]

Residents in Koriyama, one of Fukushima’s larger cities, said the flooding took them by surprise. Police were searching house-to-house to make sure nobody had been left behind or was in need of help.

“I checked the flood hazard map but it didn’t have my area as being at risk,” said Yoshinagi Higuchi, 68, who lives about 100 metres (328 feet) from one levee and waited out the flood on the second floor of his house as the ground floor filled with water.

“I heard there was a flood once before the war, but we just weren’t expecting the water to come over the levee despite all the warnings.”

Survivors described how water rose rapidly to chest height in about an hour, making it hard to escape to higher ground. Many of the dead in Fukushima were elderly, NHK said.

“Nobody from city hall has come to check on us yet,” Higuchi said, as he and his neighbours piled sodden tatami mats and other damaged furniture onto the street.

Major highways remained closed in the city as people began returning to work after the storm and a long weekend. Children in uniforms walked to school and while some stores remained closed, others were open.

Around the country, manufacturers took stock. Electronics maker Panasonic Corp said flooding had damaged its factory in a large industrial park in Koriyama.

Carmakers Nissan, Honda and Subaru said there was no major damage to their plants, while Toyota said operations were normal.

Prime Minister Shinzo Abe warned that the economic impact could be prolonged.

“The national government will continue to do everything possible so that the victims of this disaster can return to their normal lives as soon as possible,” Abe told a parliamentary committee.

Finance Minister Taro Aso said there were 500 billion yen ($4.6bn) in reserves for disaster recovery and more money would be considered if needed.

Thousands of police, fire officials and military personnel continued to search for people who may have been cut off by floodwaters and landslides, with hope diminishing that the missing would be found alive.

Though the threat of rain is expected to ease on Tuesday, temperatures are likely to drop in many areas later this week, in some cases to unseasonably low levels, NHK said.