(AP) -- Japanese authorities admitted Tuesday they'd lost track of a 113-year-old woman listed as Tokyo's oldest, days after police searched the home of the city's official oldest man - only to find his long-dead, mummified body.
Officials launched a search this week for Fusa Furuya, born in July 1897 and listed as Tokyo's oldest citizen, after it emerged her whereabouts are unknown.
Several other celebrated centenarians are also unaccounted for due to poor record-keeping and follow-up in a country that prides itself in its number of long-lived citizens but also frets about an unraveling of traditional family ties.
Officials updating their records ahead of a holiday next month honoring the elderly found that Furuya does not live at the address where she is registered, said Hiroshi Sugimoto, an official in Tokyo's Suginami ward.
Furuya's 79-year-old daughter, whose name was not disclosed, told officials she was not aware of her mother's registration at that address and said she thought her mother was with her younger brother, with whom she has lost touch. But that address just outside Tokyo turned out to be a vacant lot.
Police are also interviewing the brother and another daughter, but still have not been able to locate Furuya.
The disappearance follows last week's grisly discovery - also by officials updating the most-elderly list - that the man listed as Tokyo's oldest male, who would have been 111 years old, had actually been dead for some 30 years and his decayed body was still in his home.
Police are investigating the family of Sogen Kato for alleged abandonment and swindling his pension money. Kato is believed to have died about 32 years ago, when his family said he retreated to his bedroom, wanting to be a living Buddha.
Officials said they had not personally contacted Furuya or Kato for decades.
Authorities are also looking for a 106-year-old man who is missing in Nagoya, central Japan, Kyodo News agency reported. The Asahi newspaper said three more centenarians were unaccounted for in Tokyo.
The missing elderly people could cast doubt on the exact number of centenarians in Japan, a figure that has been rising for decades.
Officially, Japan has 40,399 people aged 100 or older, including 4,800 in Tokyo, according to an annual health ministry report last year marking the Sept. 21 holiday for the elderly.
Each centenarian receives a letter and a gift from a local government office - usually by mail. Officials in fewer than half of the country's 47 prefectures (states) routinely keep track of centenarians in person, Kyodo calculated.
Health and Welfare Minister Akira Nagatsuma urged officials to find a better way to monitor the elderly.
"Many people have doubts whether the government properly keeps track of senior citizens' whereabouts," he said. "It is important for public offices to check up on them - where and how they are - and follow through all the way."
But local officials say it is hard to keep track because families are often reluctant to receive official visits.
Many also send their elderly relatives to nursing homes without doing the proper paperwork.
"It's shocking that even relatives don't know if their parents are alive or dead," Chiba University professor Yoshinori Hiroi, an expert on public welfare, told public broadcaster NHK. "These cases were typical examples of thinning relationship among families and neighbors in Japan today."
The rapidly graying population has also fueled concerns about Japan's overburdened public pension and medical care system.
Explore further: Doctor behind 'free radical' aging theory dies