off after heavy vehicle passage, causing extensive slaughter aboard packed civilian buses. Notable Viet Cong atrocities include the massacre of over 3,000 unarmed civilians at Huế during the Tet Offensive and the killing of 252 civilians during the Đắk Sơn massacre. 155,000 refugees fleeing the final North Vietnamese Spring Offensive were reported to have been killed or abducted on the road to Tuy Hòa in 1975. According to Rummel, PAVN and Viet Cong troops killed 164,000 civilians in democide between 1954 and 1975 in South Vietnam, from a range of between 106,000 and 227,000 (50,000 of which were reportedly killed by shelling and mortar on ARVN forces during the retreat to Tuy Hoa). North Vietnam was also known for its abusive treatment of American POWs, most notably in Hỏa Lò Prison (aka the Hanoi Hilton), where torture was employed to extract confessions. Women American nurses American women served on active duty performing a variety of jobs. Early in 1963, the Army Nurse Corps (ANC) launched Operation Nightingale, an intensive effort to recruit nurses to serve in Vietnam. First Lieutenant Sharon Lane was the only female military nurse to be killed by enemy gunfire during the war, on 8 June 1969. One civilian doctor, Eleanor Ardel Vietti, who was captured by Viet Cong on 30 May 1962, in Buôn Ma Thuột, remains the only American woman unaccounted for from the Vietnam War. Although a small number of women were assigned to combat zones, they were never allowed directly in the field of battle. Unlike the men, the women who served in the military were solely volunteers. They faced a plethora of challenges, one of which was the relatively small number of female soldiers. Living in a male-dominated environment created tensions between the sexes. By 1973, approximately 7,500 women had served in Vietnam in the Southeast Asian theater. American women serving in Vietnam were subject to societal stereotypes. To address this problem, the ANC released advertisements portraying women in the ANC as "proper, professional and well protected." This effort to highlight the positive aspects of a nursing career reflected the feminism of the 1960s–1970s in the United States. Although female military nurses lived in a heavily male environment, very few cases of sexual harassment were ever reported. Vietnamese soldiers Unlike the American women who went to Vietnam, both South and North Vietnamese women were enlisted and served in combat zones. Women were