The Justice Ministry announced this month that it can't confirm the whereabouts of 230,000 centenarians listed in "koseki" family registers.

Last month, the Health, Labor and Welfare Ministry estimated that pensions were being paid out to some 800 missing people aged 85 or older.

The nationwide search for the missing elderly began when a mummified corpse was found at a home in Adachi Ward, Tokyo, in July. The man, Sogen Kato, would have been 111 years old.