KPA troops held the Americans on the hill and initially tried to move them across the river and out of the battle, but they were unable to do so because of a heavy counterattack.

The KPA commanders, concerned about the way their soldiers were treating prisoners of war, laid out stricter guidelines for handling enemy captives.

Right at the center of the Pusan Perimeter, Taegu stood at the entrance to the Nakdong River valley, an area where large numbers of KPA forces could advance while supporting one another.

The KPA planned to use the natural corridor of the Nakdong valley from Sangju to Taegu as its main axis of attack for the next push south.

From Waegwan a road runs north and south along the east bank of the Nakdong, another northeast through the mountains toward Tabu-dong, and still another southeast toward Taegu.

Hill 303 was a critical terrain feature in control of the main Pusan-Seoul railroad and highway crossing of the Nakdong, as well as of Waegwan itself.

[19] For several days, UN intelligence sources had reported heavy KPA concentrations across the Nakdong, opposite the ROK 1st Division.

Early in the morning on August 14, a KPA regiment crossed the Nakdong 6 miles (9.7 km) north of Waegwan into the ROK 1st Division sector through an underwater bridge.

[21] A patrol going to meet the climbing Korean troops called out and received in reply a blast of gunfire from automatic weapons.

[22] Some of the Americans realized that the advancing troops were KPA and were going to fire upon them, according to Privates Fred Ryan and Roy Manring, who gave their accounts when they revisited the old mortar position in 1999.

The rest of the watching Americans were not convinced that the new arrivals were enemy soldiers until the red stars became visible on their field caps.

[26] At 14:00 on August 17, a UN air strike took place, attacking the hill with napalm, bombs, rockets and machine guns.

The artillery and the air strike killed and wounded an estimated 500 KPA troops on Hill 303, with survivors fleeing in complete disorder.

The next day, August 18, US troops found the bodies of six members of the tank crews showing indications that they had been captured and executed in the same manner as the men on Hill 303.

[27] The incident on Hill 303 led UN commander General Douglas MacArthur to broadcast to the KPA on August 20, denouncing the atrocities.

MacArthur warned that he would hold North Korea's senior military leaders responsible for the event and any other war crimes.

[36] Survivors of the incident were called to testify before the committee, and the US government concluded that the KPA violated the terms of the Geneva Convention, and condemned its actions.

[22][37] Historians agree there is no evidence that the KPA High Command sanctioned the shooting of prisoners during the early phase of the war.

[33] The Hill 303 massacre and similar atrocities are believed to have been conducted by "uncontrolled small units, by vindictive individuals, or because of unfavorable and increasingly desperate situations confronting the captors.

[38] On July 28, 1950, General Lee Yong Ho, commander of the KPA 3rd Division, had transmitted an order pertaining to the treatment of prisoners of war, signed by Choi Yong-kun, Commander-in-Chief, and Kim Chaek, Commander of the KPA Advanced General Headquarters, which stated killing prisoners of war was "strictly prohibited".

An order issued by the Cultural Section of the KPA 2nd Division dated August 16 said, in part, "Some of us are still slaughtering enemy troops that come to surrender.

Therefore, the responsibility of teaching the soldiers to take prisoners of war and to treat them kindly rests on the Political Section of each unit.

"[34] The story quickly gained media attention in the United States, and the survivors' accounts received a great deal of coverage[39] including prominent magazines such as Time[22] and Life.

[23] In the years following the Korean War, the US Army established a permanent garrison in Waegwan, Camp Carroll, which is located near the base of Hill 303.

The incident was largely forgotten until Second Lieutenant David Kangas read about the incident in the Korean War history book South to the Nakdong, North to the Yalu by United States Army Center of Military History while stationed at Camp Carroll in 1985, and after checking with various US Army and local sources, he realized that the location of the massacre was unknown.

Both Ryan and Manring as well as James Rudd, the third surviving POW, had long been denied VA compensation claims for their severe injuries incurred during the execution because they had never been officially designated as prisoners of war by the US Army.

Later, the base garrison at Camp Carroll raised funds to construct a much larger memorial at the massacre site on Hill 303.

With the assistance of South Korean veterans, politicians and local citizens, the second monument was flown to the top of the hill by a US CH-47 Chinook helicopter on May 26, 2010, in preparation for the 60th anniversary of the event.

Troops garrisoned at Camp Carroll scale the hill and place flowers at the monument as a part of this service.