The advance was resumed on 11 March after the relief of 2/1 by Major Walter Gall’s Division Reconnaissance Company, reinforced by a platoon of tanks. Although the enemy withdrew from most of his positions without putting up much resistance, a patrol of George Company, 3/1, had a hot fire fight on Hill 549. Opening fire at 50 yards from camouflaged, log-faced bunkers, the Chinese killed one man and wounded nine. Marine infantrymen, supported by flat-trajectory 90mm fire, approached within grenade-throwing range to destroy five bunkers and kill 16 of the defenders. As the patrol withdrew, it called on the 11th Marines to finish the job. The cannoneers were credited with several direct hits.[124] [124] 1stMarDiv _HD_, Mar 51, 8. Chinese resistance continued to be light as the two Marine regiments occupied rather than seized ground on 12 and 13 March. By the 14th all units were dug in along Phase Line ALBANY. CCF withdrawals were also reported by other Eighth Army units. On 15 March a patrol from the 1st ROK Division of I Corps found Seoul abandoned by the enemy. The Chinese Reds had made their choice and UN forces took over a devastated city with some 200,000 civilians dragging out a miserable existence in the ruins. Dead power lines dangled over buildings pounded into rubble, and even such a famous landmark as the enormous red, brass-studded gates of the American Embassy Compound had been destroyed. It was the fourth time that Seoul had changed hands in 9 months of war. Air reconnaissance having established that the enemy had withdrawn about 15 miles to entrenched positions in the Uijongbu area, General Ridgway enlarged the mission of I Corps by directing it to advance on the left of IX Corps.[125] [125] EUSAK _Cmd Rpt_, Mar 51, 68–70. During the first phase of Operation RIPPER, from 7 to 13 March, counted casualties inflicted on the enemy by X Corps amounted to 6,543 KIA and 216 POW. IX Corps casualties during the same period were reported as 158 KIA, 965 WIA, and 35 MIA--a total of 1,158.[126] [126] IX Corps _Cmd Rpt_, Mar 51, 35–37. The total strength of the Eighth Army (less the Marines) was 185,229 officers and men in March 1951. Adding the 25,642 of the 1st Marine Division, the 4,645 of the 1st Marine Aircraft Wing, plus 11,353 of the American Air Force and 355 attached from the U.S. Navy, 227,119 Americans were serving in Korea. This does not count 13,475 South Koreans serving in various U.S. Army divisions.[127] [127] _Ibid._ The 1st Marine Aircraft Wing, with an authorized total of 728 officers and 4,216 enlisted men, had an actual strength of 626 and 4,019 respectively on 31 March 1951. Of an authorized 29 officers and 93 enlisted men from the Navy, 22 and 83 in these categories were on duty.[128] [128] FMF Status Sheet, 31 Mar 51. Troops to the number of 21,184 from the ground forces of other United Nations were represented as follows: