On May 12, 1975 a unit of the Cambodian Khmer Rouge seized a container ship, the SS "Mayagüez", on the Gulf of Siam. The botched recovery of the ship's crew on May 15 by the U.S. Marine Corps off the island of Koh Tang became known as the Mayagüez Incident, considered by historians as one of president Gerald Ford's first foreign policy setbacks. The ship was owned and operated by Sea-Land Service, which operated container service to Puerto Rico until 1975 and explains why the city's name became entangled in such a major military international incident.