002/19-09-2007-ECCC-OCIJ ЮŲŠ / No: D427 148. Duch explains that in the period immediately after 17 April 1975 - in the absence of any centre security organ – orders to execute ex-Khmer Republic officers and others who were considered enemies - were carried out by military personnel answering to zone secretaries, who received their orders from the Standing Committee.447 Zone units entering Phnom Penh448 and by zone and subordinate units entering other towns, such as Pursat in the Northwest Zone449 carried out executionzs.450 Involvement by zone, sector and district military forces in local executions continued in some parts of the country throughout the regime. This was the case at the West Zone Sector 37 and Prey Nup District security complex at Koh Kyang,451 the autonomous Sector 105 security complex at Phnom Kraol in Koh Nhek,452 and the Prey Damrei Srot district security complex in Kampong Tralach Leu District (12) of West Zone Sector 31.453 149. According to one witness, the decision to carry out purges within the military ranks was made by the Standing Committee, with Son Sen acting on the orders of Pol Pot, Nuon Chea and Ta Mok”.454 He also referred to the existence of a purge “planning meeting of the Standing Committee which comprised Pol Pot, Nuon Chea and Ieng Sary”.455 The same witness reports that the purge orders were conveyed at a meeting of military commanders convened by Pol Pot, Nuon Chea, Ta Mok and Son Sen.456 VI. 150. ARMED CONFLICT Almost immediately following the entry into Phnom Penh of the Cambodian People’s National Liberation Armed Forces (CPNLAF) on 17 April 1975, a state of international armed conflict came into existence between the Socialist Republic of Vietnam and Democratic Kampuchea. Protracted armed hostilities continued until the capture of Phnom Penh on 7 January 1979 by Vietnamese forces and beyond. 151. Although the existence of the international armed conflict between Democratic Kampuchea and the Socialist Republic of Vietnam was not officially recognised until 31 December 1977 with a statement by the Cambodian Ministry of Foreign Affairs severing diplomatic ties between the two States,457 it may be concluded that from mid-April 1975 there were ongoing, frequent and escalating armed hostilities between the two States at all times leading up to the fall of the CPK. 152. In fact, there is clear evidence demonstrating that Democratic Kampuchea and the Socialist Republic of Vietnam were engaging in armed hostilities in 1975,458 1976,459 1977460 and Extraordinary Chambers in the Courts of Cambodia, National Road 4, Choam Chao, Dangkao Phnom Penh Mailing address: P.O. Box 71, Phnom Penh; Tel: +855(0)23 218914 Fax: +855(0) 23 218941. 40