But the man was released and allowed to continue with his travel plans Wednesday after authorities determined he didn't threaten the life of the former governor or other passengers, Charleston Aviation Authority Police Chief Al Britnell said.
An airport police report says flight attendants on the Delta plane from New York said the man was making verbal threats against Sanford, who drew international attention in 2009 by vanishing for five days and confessing afterward to an affair in Argentina.
Crew members called ahead to have officers waiting at the gate. Britnell says the man from Cold Spring Harbor, N.Y., yelled about having friends in politics and seemed irritated with passengers including Sanford.
Britnell says the man was questioned and released with no charges.
Sanford, who has not spoken publicly about his professional plans after leaving the governor's mansion, did not immediately respond to a message seeking comment.