 Many of the newest American-trained Chinese units and supplies were forcibly locked in the Burmese theater under Joseph Stilwell set by terms of the Lend-Lease Agreement.In Operation Kogo, 390,000 Chinese soldiers, led by General Tang Enbo (), were deployed to defend the strategic position of Luoyang.The 3rd Tank Division of the IJA crossed the Yellow River around Zhengzhou in late April and defeated Chinese forces near Xuchang, then swung around clockwise and besieged Luoyang.