On 23 January 1968 North Korea

North Korea

The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...

n patrol boats supported by two MiG-21 fighters captured the USS Pueblo

USS Pueblo (AGER-2)

USS Pueblo is an American ELINT and SIGINT Banner-class technical research ship which was boarded and captured by North Korean forces on January 23, 1968, in what is known as the Pueblo incident or alternatively as the Pueblo crisis or the Pueblo affair. Occurring less than a week after President...

 northeast of the North Korean island of Ung-do

Pansong archipelago

The Pansŏng Archipelago is a chain of islands located off the coast of Cholsan county, North Korea. The chain includes North Korea's largest island, Sinmi-do...

. The seizure of the Pueblo lead to President Lyndon Johnson

Lyndon B. Johnson

Lyndon Baines Johnson , often referred to as LBJ, was the 36th President of the United States after his service as the 37th Vice President of the United States...

 ordering a show of force with a massive deployment of U.S. air and navy assets to Korea. The airlift and deployment of 200+ aircraft was code named Operation Combat Fox while the deployment of six aircraft carriers plus support vessels was code named Operation Formation Star. The operations were supported by the partial mobilization of reservists for the first time since the Cuban Missile Crisis. CIA

Central Intelligence Agency

The Central Intelligence Agency is a civilian intelligence agency of the United States government. It is an executive agency and reports directly to the Director of National Intelligence, responsible for providing national security intelligence assessment to senior United States policymakers...

 A-12 Oxcart reconnaissance overflights over North Korea were used to monitor a feared retaliatory mobilization of North Korean forces and when these flights revealed no mobilization or large scale deployments by North Korean forces, Operation Combat Fox forces were stood down.