Civil war People's Republic of Kampuchea

mountains along cambodian-thai border north of road between sisophon , aranyaprathet. 1 of areas khmer rouge insurgents hid @ time of k5 plan.

disoriented cambodian refugees refugee camps in aranyaprathet, thailand, forcefully sent across border beginning in 1980 , many of them ended in areas under khmer rouge control.

the process organised pro-democratic kampuchea cadres, presented press voluntary . undermining of people s republic of kampuchea supported united states government, took dim view of existing pro-vietnamese cambodian regime, countries malaysia, thailand , singapore, representative exhorted dispirited refugees go , fight.

the civil war followed wet season/dry season rhythm after 1980. heavily armed vietnamese forces conducted offensive operations during dry seasons, , chinese-backed insurgency held initiative during rainy seasons. in 1982, vietnam launched major offensive against main khmer rouge base @ phnom malai in cardamom mountains. operation met little success.

in 1984–85 dry season offensive, vietnamese again attacked base camps of 3 anti-prk groups. time vietnamese succeeded in eliminating khmer rouge camps in cambodia , drove insurgents neighbouring thailand. before retreating khmer rouge laid down numerous landmines , cut down giant trees block roads in thick jungle along thai-cambodian border causing heavy deforestation. vietnamese concentrated on consolidating gains through k5 plan, extravagant , labour-intensive attempt seal guerrilla infiltration routes country means of trenches, wire fences, , minefields along virtually entire thai-cambodian border. k5 border defence project, designed vietnamese general lê Đức anh, commander of vietnamese forces in cambodia, irritated cambodian farmers , ended being psychologically counterproductive prk. large swathes of formerly inaccessible tropical forests destroyed, leaving negative ecological legacy.

despite of vietnamese army, of soviet, cuban , vietnamese advisers, heng samrin had limited success in establishing prk regime in face of ongoing civil war. security in rural areas tenuous, , major transportation routes subject interdiction sporadic attacks. presence of vietnamese throughout country , intrusion cambodian life added fuel traditional cambodian anti-vietnamese sentiment.

in 1986, hanoi claimed have begun withdrawing part of occupation forces. @ same time, vietnam continued efforts strengthen client regime, prk, , military arm, kampuchean people s revolutionary armed forces (kpraf). these withdrawals continued on next 2 years, although actual numbers difficult verify. vietnam s proposal withdraw remaining occupation forces in 1989–90—one of repercussions of dismemberment of soviet bloc result of , chinese pressure—forced prk begin economic , constitutional reforms in attempt ensure future political dominance. in april 1989, hanoi , phnom penh announced final withdrawal take place end of september same year.