Complex sentence: Intelligence estimates placed the greatest concentration of enemy troops in this area, some estimates being as high as four enemy divisions and several armored regiments, all of 40,000 men, who were reportedly using the area to stage their attack on Taegu.
Split into simpler sentences: Intelligence estimates placed the greatest concentration of enemy troops in this area, with some estimates being as high as four enemy divisions and several armored regiments. All up, 40,000 men were reportedly using the area to stage their attack on Taegu.