Exploiting this weakness, the KPA 9th and 4th Divisions attacked to Yongsan, a village east of the river and the gateway to the UN lines of supply and reinforcement for the Pusan Perimeter.

In three days of fierce fighting, the Army and Marine forces were able to push the KPA out of the town and destroy the two attacking divisions.

[2] From their initial June 25 offensive to fights in July and early August, the KPA used these tactics to effectively defeat any UN force and push it south.

[4] Fed by intelligence from the Soviet Union, the North Koreans were aware of the UN forces building up along the Pusan Perimeter and that they must conduct an offensive soon or they could not win the battle.

[19] On the morning of September 1 the 1st and 2nd Regiments of the KPA 9th Division, in their first offensive of the war, stood only a few miles short of Yongsan after a successful river crossing and penetration of the US line.

[20][21] The 3rd Regiment had been left at Inch'on, but division commander Major General Pak Kyo Sam felt the chances of capturing Yongsan were strong.

[23][24] Crossing the river behind it came the 4th Division, a greatly weakened organization, far understrength, short of weapons, and made up mostly of untrained replacements.

[20] Division commander Major General Laurence B. Keiser in this emergency attached the 2nd Engineer Combat Battalion to the regiment.

Approximately 2 miles (3.2 km) west of Yongsan an estimated 300 KPA troops engaged A Company in a fire fight.

[23] Meanwhile, with the approval of the Assistant Division Commander Brigadier General Joseph S. Bradley, D Company moved to the hill immediately south of and overlooking Yongsan.

The hill occupied by D Company was in reality the western tip of a large mountain mass that lay southeast of the town.

[23] The road to Miryang came south out of Yongsan, bent around the western tip of this mountain, and then ran eastward along its southern base.

[29] The fire of the 18 Bazookas plus that from machine guns and the small arms of the company inflicted very heavy casualties on the KPA, who desperately tried to clear the way for a push eastward to Miryang.

[29] While this battle raged during the morning at Yongsan, commanders reorganized about 800 men of the 9th Infantry who had arrived in that vicinity from the overrun river line positions.

[34] At 09:35 September 2, while the KPA were attempting to destroy the engineer troops at the southern edge of Yongsan and clear the road to Miryang,[33] Eighth United States Army commander Lieutenant General Walton Walker spoke by telephone with Major General Doyle O. Hickey, Deputy Chief of Staff, Far East Command in Tokyo.

[40] At dawn September 3, A Company attacked to gain the high ground which was part of the designated Marine line of departure.

The company with help from Marine tank fire eventually gained its objective, but this early morning battle for the line of departure delayed the planned attack.

[42] The Marine attack started at 08:55 across the rice paddy land toward KPA-held high ground 0.5 miles (0.80 km) westward.

[39] Air strikes, artillery concentrations, and machine gun and rifle fire of the 1st Battalion now caught KPA reinforcements in open rice paddies moving up from the second ridge and killed most of them.

[42] North of the road the 2nd Battalion had a harder time, encountering heavy KPA fire when it reached the northern tip of Hill 116, 2 miles (3.2 km) west of Yongsan.

Tanks and ground troops advancing along the road found it littered with KPA dead and destroyed and abandoned equipment.

[39][45] In bringing his platoon from an outpost position to the relief of the company, Sergeant First Class Loren R. Kaufman encountered an encircling KPA force on the ridge line.

US artillery fire concentrated in front of the 9th Infantry helped greatly in repelling the KPA in this night and day battle.

As the attack progressed, the marines approached Obong-ni Ridge and the 9th Infantry neared Cloverleaf Hill where they had fought tenaciously during the First Battle of Naktong Bulge the month before.

[47] Assault teams of B Company and the 1st Battalion with 3.5-inch Bazookas rushed into action, took the tanks under fire, and destroyed both of them, as well as an armored personnel carrier following behind.

[50] He had vainly protested against releasing the brigade, believing he needed it and all the troops then in Korea if he were to stop the KPA offensive against the Pusan Perimeter.

[52][53] The American counteroffensive of September 3–5 west of Yongsan, according to prisoner statements, resulted in one of the bloodiest debacles of the war for a KPA division.

The exact number of KPA casualties at Yongsan is impossible to determine, but a substantial amount of the attacking force was lost there.

[58] The 1st Provisional Marine Brigade suffered 185 killed and around 500 wounded during the Battle of Pusan Perimeter, most of which probably occurred at Yongsan.

[56] Once again the fatal weakness of the KPA had cost it victory after an impressive initial success-its communications and supply were not capable of exploiting a breakthrough and of supporting a continuing attack in the face of massive air, armor, and artillery fire that could be concentrated against its troops at critical points.