TOKYO — Japanese officials say that at least $4.9 billion is unaccounted for in a financial scandal at Olympus and are investigating whether much of that money went to companies with links to organized crime.

In a memo prepared by investigators and circulated at a recent meeting of officials from Japan’s Securities and Exchange Surveillance Commission, the Tokyo prosecutor’s office and the Tokyo Metropolitan Police Department, officials say they are trying to determine whether Olympus worked with organized crime syndicates to obscure billions of dollars in past investment losses and then paid them exorbitant sums for their services.

The memo — a copy of which was obtained by The New York Times from a person close to the official investigation — appears to link the Olympus losses for the first time to organized crime groups.

It also suggests that investigators believe illicit payouts from Olympus went far beyond the roughly $1.4 billion in merger fees and acquisition payments that have come under recent scrutiny, potentially making it one of the biggest scandals in Japanese corporate history.