In response to international pressure, and to avoid engaging in a debilitating conflict with various local armed resistance groups, Vietnam began withdrawing its military forces from Kampuchea as early as 1982. But the withdrawal process lacked international verification, so foreign observers simply dismissed Vietnam's movement of troops as mere rotations. In 1984, in order to disengage from Kampuchea, Vietnam unveiled a five-phase strategy known as the K5 Plan. The plan was authored by General Le Duc Anh, who had led the Vietnamese campaign in Kampuchea. The first phase required the Vietnamese military to capture the bases of armed groups in western Kampuchea and along the border with Thailand. The following phases included sealing off the border with Thailand, destroying local resistance groups, providing security for the population, and building up the Kampuchean People's Revolutionary Armed Forces. Foreign observers believed that the Vietnamese Army completed the first phase of the K5 Plan during the dry season offensive of 1984–85, when the base camps of several anti-Vietnamese resistance groups were overrun. Afterwards, the majority of ten Vietnamese divisions were assigned to operations on the frontiers, with the remainder staying in major provinces to protect the local population and to train the Kampuchean armed forces.