Battle of the Soyang River

The Battle of the Soyang River, also referred to as the "May Massacre",^{: 330–334} or Battle of Hyeon-ri (Korean: 현리 전투, Chinese: 縣里戰役) in Korean and Chinese was fought during the Korean War between United Nations Command (UN) and the Chinese People's Volunteer Army (PVA) and Korean People's Army (KPA) during the Spring Offensive of April–May 1951. The attack took place across the entire front but with the main thrust below the Soyang River in the Taebaek Mountains. The objective of the main effort was to sever the six Republic of Korea Army (ROK) divisions on the eastern front from the remainder of the US Eighth Army and annihilate them and the US 2nd Infantry Division. Secondary attacks would be mounted by PVA and KPA forces across the entire front.

The attack was launched on 16 May 1951 and succeeded in swiftly pushing back the ROK I Corps which retreated in good order and III Corps which was routed, while the US 2nd Infantry Division to their left mounted a stronger defense before gradually giving up ground. By 19 May the PVA/KPA advance was losing momentum due to reinforcement of the UN forces, supply difficulties and mounting losses from UN air and artillery strikes. On 20 May the UN launched a counterattack on the west of the front and the PVA/KPA began to withdraw after suffering heavy losses with the offensive coming to an end on 22 May.