July 31 (UPI) -- Former Teamsters Union President Jimmy Hoffa disappeared 50 years ago at age 62, but the FBI's Detroit Field Office continues seeking information for its ongoing investigation. The FBI investigates missing persons cases that might involve violations of federal law, such as kidnapping, organized crime and other criminal acts. "As the 50th anniversary of Mr. Hoffa's disappearance approaches, the FBI remains steadfast in its commitment to pursuing all credible leads," said