Operation AS-3

'AS-3' was a Japanese naval sweep against US submarines in the Strait of Tsushima, between Japan and Korea (9 June 1945 onward).

The sweep was undertaken by the Imperial Japanese navy’s 102nd Escort Squadron, which included the escort vessels CD-41 and Yashiro, which operated in the area to the south-east of Mokpo in Korea. The sweep found no US submarines.