 <unk> with the launching of Toan Thang 44 , the two battalions of the 3rd Brigade , U.S. 9th Infantry Division , crossed the border 48 kilometers southwest of the Fishhook into an area known as the Dog 's Face from 7 through 12 May . The only significant contact with PAVN forces took place near the hamlet of <unk> , where 51 North Vietnamese were killed and another 21 were captured . During the operation , the brigade lost eight men killed and 22 wounded . It was already too late for thousands of ethnic Vietnamese murdered by Cambodian persecution , but there were tens of thousands of Vietnamese still within the country who could now be evacuated to safety . South Vietnamese President Nguyễn Văn Thiệu arranged with Lon Nol to <unk> as many as were willing to leave . The new relationship did not , however , prevent the Cambodian government from stripping the Vietnamese of their homes and other personal property before they left . 
