Original sentence: By 17 May, Quảng Trị City was retaken, but the South Vietnamese military ran out of steam.During these operations North Vietnamese suffered approximately 100,000 casualties while the South Vietnamese suffered 30,000 fatalities during the fighting.Regardless, the effort failed to halt the fall of Quảng Trị City on 2 May, seemingly sealing the fate of the four northernmost provinces.The answer came on 30 March 1972 when 30,000 PAVN troops, supported by more than 300 tanks crossed the border and invaded Quảng Trị Province.The request was granted by the Joint Chiefs of Staff, The area fell under the auspices of "Operation Tiger Hound"
Edited sentence: By 17 May, Quang Tri City was retaken, but the South Vietnamese military ran out of steam.During these operations North Vietnamese suffered approximately  100,000 casualties while the South Vietnamese lost 30,000 men killed during the fighting.Regardless, the effort failed to halt the fall of Quang Tri City on 2 May, seemingly sealing the fate of the four northernmost provinces.The answer came on 30 March 1972 when 30,000 PAVN troops, supported by more than 300 tanks crossed the border and invaded Quang Tri Province.The request was granted by the Joint Chiefs of Staff and the area came under the auspices of the "Operation Tiger Hound"