Japanese officials say deaths of the elderly are going unreported whilst families continue to draw their deceased relatives' pensions.
The warning comes after a national audit into family registries found a man believed to be Japan's oldest resident had actually been dead for at least 30 years.
Officials went to visit Sogan Kato, believed to be 111, to congratulate him on his birthday, but found only his decomposing remains. Mr Kato had received the equivalent of £70,000 in pension payments since his wife's death in 2004, and some of this money had been withdrawn.
According to the audit, 230,000 people listed as being aged over 100 are unaccounted for. The authorities say some of those missing would be 150 years old if found alive, and there are now concerns their deaths went unreported by families looking to defraud the pensions system.
The Justice Ministry said some of those missing may have died as early as during or after World War II, and others may have emigrated without informing the local authorities.
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