 The rugged terrain of the mountains prevented the North Korean forces from conducting the enveloping maneuvers they had used so effectively against other troops, and their advantages in numbers and equipment had been negated in the fight.By July 28, the division was still embroiled in this fight and the 766th bypassed it and moved toward Chinbo on the left flank of the city.However the 766th had suffered significant setbacks at Yongdok, with substantial losses due to American and British naval artillery fire.