Force Northrop F-5Es and crashed in a rice field near Prachinburi, Thailand during an intelligence-gathering mission from Phnom Penh, reportedly killing one of 13 onboard Early March: A spate of incidents along the border, culminating in the intrusion of 300 Vietnamese troops and the killing of a number of Thai Border Patrol Police. 21 October: Vietnamese gunners opened fire on a Thai reconnaissance plane near the border, but did not hit the aircraft. The plane returned to its base inside Thailand. 1983 January: Cambodian government troops, backed by Vietnamese units, conducted a major offensive against the Coalition Government of Democratic Kampuchea, which united three resistance factions. The fighting spilled over onto Thai soil. More than 47,000 Cambodians fled to Thailand. 16 January: Vietnamese troops recaptured the hamlet of Yeang Dangkum, east of Nong Chan. Insurgents from the non-Communist Khmer People's National Liberation Front (KPNLF) captured the hamlet on 26 December and held it as part of a series of initiatives at year's end. 21 January: Vietnamese artillery attack forced the KPNLF base in the 0'Bok pass to move into Thailand. Non-combatants return at the end of the month. 31 January – 1 February: With heavy artillery support, 4,000 armour-led Vietnamese troops launched an assault against Nong Chan, one of the largest refugee camps on the border, destroying it. Ground fighting was reported outside the camp between Vietnamese troops based in Cambodia and about 2,000 KPNLF guerrillas. At the same time the Vietnamese kept up a steady barrage of shells, rockets and mortars. At least 50 shells landed in Thai territory, killing a 66-year-old farmer and damaging several houses and a Buddhist temple. The refugee population of about 24,000 fled with unknown casualties while MOULINAKA units were brushed aside, and KPNLF forces withdrew after a 36-hour fight. The Khao-I-Dang ICRC hospital received over 100 civilian wounded. 31 March: 1,000 Vietnamese troops, augmented by about 600 PRK "people's volunteers," attacked the Khmer Rouge refugee settlements of Phnom Chat and Chamkar Kor, aided by artillery, rocket, and Soviet T-54 tank fire. Thai officials reported that the Vietnamese attacks again had resulted in "spillovers" with Vietnamese artillery and mortar shells falling into adjacent Thai territory. Vietnamese troops clashed with Thai forces for several days, drawing Bangkok into a defensive campaign. Intense exchange of artillery and tank fire killed 30 civilians and injured some 300 persons. Approximately 22,000 Cambodian civilians fled to Thailand for refuge.