The thief also had a fake police motorcycle.
On Dec. 10, 1968, a policeman on a white motorcycle pulled over a car which was transporting bonuses for local Toshiba employees. The officer said the branch manager's house had been blown up, and police had received a warning that there was dynamite underneath the car. This seemed credible because the men in the car knew of a blackmail threat four days before.
The officer looked under the car to search. Suddenly, smoke and flames began pouring out from underneath. The officer yelled that a bomb was going to explode. The men fled.
The fake policeman drove away in the car containing with four metal boxes filled with 294,307,500 yen.
This was the largest single "highway" theft in Japanese history, and despite an investigation involving 170,000 actual police officers, the thief was never found.
There have been many theories about this unsolved case. How many were involved? Was it an inside job? Was the CIA somehow responsible? The statute of limitations has now expired, so the thief could come forward without penalty, but so far, the identity of the criminal (or criminals) remains a mystery.