The Tet Offensive began on 30 January 1968 , as over 100 cities were attacked by over 85,000 enemy troops , including assaults on key military installations , headquarters , and government buildings and offices , including the U.S. Embassy in Saigon . U.S. and South Vietnamese forces were initially shocked by the scale , intensity and deliberative planning of the urban offensive , as infiltration of personnel and weapons into the cities was accomplished covertly ; the offensive constituted an intelligence failure on the scale of Pearl Harbor . Most cities were recaptured within weeks , except the former capital city of Huế in which NVA and Viet Cong troops captured most of the city and citadel except the headquarters of the 1st Division and held on in the fighting for 26 days . During that time , they had executed approximately 2,800 unarmed Huế civilians and foreigners they considered to be enemy 's spies . In the following Battle of Huế American forces employed massive firepower that left 80 percent of the city in ruins . Further north , at Quảng Trị City , the ARVN Airborne Division , the 1st Division and a regiment of the US 1st Cavalry Division had managed to hold out and overcome an assault intended to capture the city . In Saigon , Viet Cong/NVA fighters had captured areas in and around the city , attacking key installations and the neighbourhood of Cholon before members of the ARVN Rangers dislodged them after three weeks . During one battle , Peter Arnett reported an infantry commander saying of Bến Tre ( laid to rubble by U.S. attacks ) that " it became necessary to destroy the village in order to save it . " During the first month of the offensive , 1,100 Americans and other allied troops , 2,100 ARVN , and 14,000 civilians were killed . By the end of the first offensive , after two months , nearly 5,000 ARVN and over 4,000 U.S. forces had been killed , with total wounded of 45,820 and an unknown number of NVA/Viet Cong casualties , with some U.S. authors claiming the NVA and Viet Cong suffered 17,000 KIA and 32,000 total casualties including wounded . A month later a second offensive known as the Phase II/May Offensive was launched ; although less widespread , it demonstrated the Viet Cong were still capable of carrying out orchestrated nationwide offensives . Two months later a third offensive was launched , the Phase III/August Offensive . The NVA 's own official records of their losses across all three offensives was 45,267 killed and 111,179 total casualties . By then it had become the bloodiest year of the war up to that point . The failure to spark a general uprising , and the fact that no units within the ARVN defected , meant both war goals of Hanoi had fallen flat at enormous costs
executed approximately 2,800 unarmed Huế
Massacre at Huế
Vietnam War