<P> General Ridgway was appointed Supreme Commander, Korea; he regrouped the UN forces for successful counterattacks, while General James Van Fleet assumed command of the U.S. Eighth Army . Further attacks slowly depleted the PVA and KPA forces; Operations Courageous (23--28 March 1951) and Tomahawk (23 March 1951) were a joint ground and airborne infilltration meant to trap Chinese forces between Kaesong and Seoul . UN forces advanced to "Line Kansas", north of the 38th parallel . The 187th Airborne Regimental Combat Team's ("Rakkasans") second of two combat jumps was on Easter Sunday, 1951, at Munsan - ni, South Korea, codenamed Operation Tomahawk . The mission was to get behind Chinese forces and block their movement north . The 60th Indian Parachute Field Ambulance provided the medical cover for the operations, dropping an ADS and a surgical team and treating over 400 battle casualties apart from the civilian casualties that formed the core of their objective as the unit was on a humanitarian mission . </P> <P> The Chinese counterattacked in April 1951, with the Fifth Phase Offensive, also known as the Chinese Spring Offensive, with three field armies (approximately 700,000 men). The offensive's first thrust fell upon I Corps, which fiercely resisted in the Battle of the Imjin River (22--25 April 1951) and the Battle of Kapyong (22--25 April 1951), blunting the impetus of the offensive, which was halted at the "No - name Line" north of Seoul . On 15 May 1951, the Chinese commenced the second impulse of the Spring Offensive and attacked the ROK Army and the U.S. X Corps in the east at the Soyang River . After initial success, they were halted by 20 May . At month's end, the U.S. Eighth Army counterattacked and regained "Line Kansas", just north of the 38th parallel . The UN's "Line Kansas" halt and subsequent offensive action stand - down began the stalemate that lasted until the armistice of 1953 . </P> <P> For the remainder of the Korean War the UN Command and the PVA fought, but exchanged little territory; the stalemate held . Large - scale bombing of North Korea continued, and protracted armistice negotiations began 10 July 1951 at Kaesong . On the Chinese side, Zhou Enlai directed peace talks, and Li Kenong and Qiao Guanghua headed the negotiation team . Combat continued while the belligerents negotiated; the UN Command forces' goal was to recapture all of South Korea and to avoid losing territory . The PVA and the KPA attempted similar operations, and later effected military and psychological operations in order to test the UN Command's resolve to continue the war . </P> <P> The principal battles of the stalemate include the Battle of Bloody Ridge (18 August--15 September 1951), the Battle of the Punchbowl (31 August - 21 September 1951), the Battle of Heartbreak Ridge (13 September--15 October 1951), the Battle of Old Baldy (26 June--4 August 1952), the Battle of White Horse (6--15 October 1952), the Battle of Triangle Hill (14 October--25 November 1952), the Battle of Hill Eerie (21 March--21 June 1952), the sieges of Outpost Harry (10--18 June 1953), the Battle of the Hook (28--29 May 1953), the Battle of Pork Chop Hill (23 March--16 July 1953), and the Battle of Kumsong (13--27 July 1953). </P>

When did the korean war became a stalemate