Battle of Kaesong–Munsan

The Battle of Kaesong–Munsan–Bongilcheon (Hangul: 개성–문산–봉일천 전투; Hanja: 開城–汶山–奉日川 戰鬪) was a series of battles that occurred along the western region of the 38th parallel between 25 and 28 June 1950, and it was a part of the Operation Pokpoong (North Korea) and Operation Western Region (South Korea) that marked the beginning of the Korean War. On 25 June, the 1st Infantry and the 6th Infantry Division, supported by the 203rd Armored Regiment and the 3rd 38-Guard Brigade, of the Korean People's Army Ground Force (KPAGF) I Corps launched a surprise supporting attack on the Republic of Korea Army (ROKA) 1st Infantry Division to surround Seoul from the west while the KPA I Corps main attack concurred in the west central region of the 38th parallel defended by the ROK 7th Infantry Division.

North Korea
Korean People's Army Ground Force
 * 1st Infantry Division - Brigadier General Choe Kwang
 * 2nd Infantry Regiment - Colonel Kim Yang-chun
 * 3rd Infantry Regiment - Colonel Lee Chang-kwon
 * 14th Infantry Regiment - Colonel Hwang Sok
 * Divisional Artillery Regiment - Colonel Hyon Hak-pong
 * 6th Infantry Division - Brigadier General Pang Ho-san
 * 1st Infantry Regiment - Colonel Kim Hu-chin
 * 13th Infantry Regiment - Colonel Han Il-rae
 * 15th Infantry Regiment - Colonel Cho Kwan
 * Divisional Artillery Regiment - Lieutenant Colonel Lee Min

South Korea
Due to the reorganisation of the Republic of Korea Army, the quality of training of the ROK 1st Infantry Division was lower than that of other divisions. The 11th Infantry Regiment and the 12th Infantry Regiment just began battalion-sized training; only 2 battalions from the 13th Infantry Regiment were at the last phase of the training, and 1 battalion was sent away for the field training.

In addition, 57% of the soldiers were given leave on June 24. Under the circumstances, the 12th Infantry Regiment had to defend 80 km frontline with only 800 troops. Moreover, heavy firearms and vehicles were sent to the rear for reorganization, and the division commander Paik Sun-yup was absent at the scene for training since June 14.

Republic of Korea Army
 * 1st Infantry Division - Colonel Paik Sun-yup
 * 11th Infantry Regiment - Colonel Choe Kyung-rok
 * 12th Infantry Regiment - Lieutenant Colonel Kim Jeom-gon
 * 13th Infantry Regiment - Colonel Kim Ik-ryeol