When the Manchurian operation began on August 9 the 393rd was a separate division located on the extreme southern flank of 25th Army, which was now part of the 1st Far Eastern Front. That day the 108th and 113th Fortified Regions captured Japanese positions across the Hunchun and Tumen rivers, securing a bridgehead over the Tumen at Kyonghung, north of the old 1938 battlefield at Lake Khasan. On the 11th the division, less the 541st Rifle Regiment, reinforced the 113th, fighting along the northeast coast of Korea. Early the next morning the 393rd conducted a motorized attack through the lines of the 113th against the Japanese 101st Separate Infantry Regiment south of Chonghak, which withdrew westward. Within hours, at 0900, the division's forward detachment assisted a naval task force in securing the port of Unggi. It left one battalion as a garrison there and continued to the port of Najin, which it occupied on August 14. Active operations in Korea ended two days later as the division was securing a mountain pass 12km north of Chongjin before advancing into the city at 1500 hours, linking up with the 355th Rifle Division which had been landed there by sea.