On January 5, 1987, a gunfire by Vietnamese troops of the Socialist Republic of Vietnam gunned down Chinese soldier Song Jianping of the Chinese People's Liberation Army shortly after he paused at a Chinese military position on the Laoshan front in the Yunnan Province border.

　　On January 5, 1987, just after Chinese soldier Song Jianping paused for a smoke break at a Chinese military position on the Laoshan frontline on the Yunnan Province border, Vietnamese gunfire shot and killed Chinese soldier Song Jianping. While the fighting continued, a Chinese military colleague attempted to posthumously treat Song Jianping's body by covering him with a cotton overcoat, a cotton greatcoat.

　The Sino-Vietnamese War broke out on February 17, 1979 and lasted until March 16, 1979, when Chinese forces launched a self-defense counterattack war against North Vietnamese forces. China and North Vietnam had been comrades-in-arms during the Vietnam War. China enthusiastically celebrated the birth of the Socialist Republic of Vietnam in April 1975. However, the separation between the two countries surfaced soon after the end of the Vietnam War, when the new Vietnamese government demanded possession of the Xisha and Nansha archipelagos, which had been disputed between China and Vietnam since the early 1970s. The Vietnamese side demanded that the border be negotiated, stating that the approximately 1,100-km border had not yet been demarcated. Before any talks could be held, Vietnam began persecuting the hundreds of thousands of urban residents of Chinese descent in the south of the country in 1977, forcing them to leave their homes for rural villages. Vietnam also caused repeated incidents of encroachment by China in the border region. The international context was the Sino-Soviet conflict, and after the Vietnam War, Vietnam rapidly moved closer to China's number one enemy, the Soviet Union. Stirring Chinese caution, it invaded pro-Chinese Cambodia in December 1978. The Sino-Vietnamese War, a cross-border attack by Chinese forces that exceeded the limits of Chinese patience, lasted about a month until the withdrawal was completed on March 16, 1979. About 26,000 Chinese troops were killed and about 30,000 Vietnamese troops were killed in action. Thereafter, fierce offensives and defenses were repeated across the border.

　The Sino-Vietnamese conflict continued to be a series of border and naval clashes between the People's Republic of China and the Socialist Republic of Vietnam from 1979 to 1991, even after the Sino-Vietnamese War of 1979. The conflict lasted from the end of the Sino-Vietnamese War until the normalization of diplomatic relations in 1991. After the Sino-Vietnamese War, the Chinese People's Liberation Army withdrew from Vietnam in March 1979. Chinese troops occupied 60 square kilometers of disputed territory controlled by Vietnam before the outbreak of hostilities. In some areas, such as the area around the Friendship Gate near the city of Long Son (Lạng Sơn), Chinese forces occupied territory of little military value but of symbolic value. Elsewhere, Chinese forces occupied strategic positions of military importance as springboards for attacking Vietnam. The occupation of border areas by Chinese forces angered Vietnam and became the starting point for a series of border disputes between Vietnam and China to gain control of border areas. The Sino-Vietnamese conflict continued until 1991, reaching its peak in 1984-1985; relations between the two countries gradually returned to normal in the early 1990s with Vietnam's withdrawal from Cambodia and the dissolution of the Soviet Union; by 1991, the two countries declared normalization of diplomatic relations and the border conflict ended.