On August 14, 1962, a police officer directed a mail truck on a Massachusetts highway to make a detour. The mail truck was carrying $1.5 million in cash and silver certificates from Cape Cod banks to the Federal Reserve Bank in Boston. The officer was a thief in disguise who led the truck to his armed accomplices. They made off with the money, leaving the postal driver and his guard tied in their truck.
Three of the gunmen were indicted but not convicted because a key witness disappeared, possibly murdered by his criminal associates. The money has never been recovered.