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"""However, the following day, China announced that it would not move deeper into Vietnam, apparently after meeting fierce and unexpectedly harsh resistance by the well trained and experienced Vietnamese forces, supplied with American technology left behind from the Vietnam War. Confident that the threat of invasion had been a success, the Chinese retreated, leaving a path of destruction spanning 500 kilometers (310 mi) in their wake.[49]. Chinese total losses were estimated higher than those of the Vietnamese (12–50,000 compared to the Vietnamese death toll of approximately 10,000), ......."
The number of casualties during the war is disputed. Vietnamese source claimed the PLA had suffered 62,500 total casualties, 550 military vehicles, and 115 artillery pieces destroyed;[49] while Chinese democracy activist Wei Jingsheng told western media in 1980 that the Chinese troops had suffered 9,000 deaths and about 10,000 wounded during the war.[50] New leaks from Chinese military sources indicated that China only suffered 6,954 dead,[5][9][51]
Vietnamese casualties
Like their Chinese counterparts, the Vietnamese government has never announced any information on its actual military casualties. China estimated that Vietnam lost 57,000 soldiers and 70,000 militia members during the war.[50][52][53] The official Nh?n D?n newspaper claimed that Vietnam suffered more than 100,000 civilian deaths during the Chinese invasion[54][55] and earlier on May 17, 1979, reported statistics on heavy losses of industry and agriculture properties.[54]