In an effort to secure the American supply line between Mindoro and Lingayan Gulf, TF 38 steamed through the Luzon Strait into the South China Sea to strike at nearby Japanese defensive installations and shipping. Although plagued by bad weather, the American carriers raided Japanese shipping along the coast of Indochina on 12 January and struck at airfields and ports on Formosa, Hainan, and in China on the 15th and 16. After a brief excursion north to fly photographic missions over Okinawa, the task force returned to Ulithi on 27 January.