[3] The massacre was committed by the government forces of president Syngman Rhee and falsely blamed on the communists led by North Korean leader Kim Il Sung.

[14] According to Kim Mansik, who was a military police superior officer, President Syngman Rhee ordered the execution of people related to either the Bodo League or the South Korean Workers Party on 27 June 1950.

[16][17] Retreating South Korean forces and anti-communist groups[18] executed the alleged communist prisoners, along with many of the Bodo League members.

[12] Retired South Korean Adm. Nam Sang-hui confessed that he authorized 200 victims' bodies to be thrown into the sea, saying, "There was no time for trials for them.

[4][24] Great Britain raised this issue with the U.S. at a diplomatic level, causing Dean Rusk, Assistant Secretary of State for Far Eastern Affairs, to inform the British that U.S. commanders were doing "everything they can to curb such atrocities".

[25][10] The Associated Press conducted extensive archival research and found documents classified "secret" and "filed away" by the Pentagon and State Department in Washington, that had indicated the US commander Gen. Douglas MacArthur made no attempts to curb the summary mass killings.

[27][7][28] After the UN offensive in which South Korea recovered its occupied territories, the police and militia groups executed suspected North Korean sympathizers.

In December, British troops saved civilians lined up to be shot by South Korean officers and seized one execution site outside Seoul to prevent further massacres.

[22][30][3] South Korea's Truth and Reconciliation Commission documented testimonies of those still alive and who took part in the executions, including former Daejeon prison guard Lee Joon-young.