As the American units began to break out of the Pusan Perimeter, they suffered numerous casualties to mines that the Koreans laid in their path of advance. In one incident, as Company A spearheaded the advance on the Taegu-Waegwan road, the unit lost nearly 75% of its tanks to mines in order to clear the road for the follow-on infantry. On 21 September, tanks of the 70th Tank Battalion continued to spearhead the 1st Cavalry's northward advance, at times outpacing both supporting infantry as well as their own supply line. Tanks of Company C led the advance of Task Force Lynch (after Lieutenant Colonel James H. Lynch), consisting of troops of 3rd Battalion 7th Cavalry Regiment and other units, in their drive toward the units breaking out from the Inchon landings. On 26 September, Task Force Lynch drove 106 miles before linking up at Chongji with elements of the 31st Infantry Regiment, 7th Infantry Division, one of the units which had landed at Inchon.