The Soviet–Afghan War was a protracted armed conflict fought in the Soviet-controlled Democratic Republic of Afghanistan (DRA) from 1979 to 1989. It saw extensive fighting between the occupying forces of the Soviet Union, the DRA and allied paramilitary groups against the Afghan mujahideen, foreign fighters, and smaller groups of anti-Soviet Maoists. While the mujahideen were backed by various countries and organizations, the majority of their support came from Pakistan, the United States (as part of Operation Cyclone), the United Kingdom, China, Iran, and the Arab states of the Persian Gulf. Combat took place throughout the 1980s, mostly in the Afghan countryside. The conflict led to the deaths of between 562,000 and 2,000,000 Afghans, while millions more fled from the country as refugees; most externally displaced Afghans sought refuge in Pakistan and in Iran. Approximately 6.5% to 11.5% of Afghanistan's erstwhile population of 13.5 million people (per the 1979 census) is estimated to have been killed over the course of the conflict. The Soviet–Afghan War caused grave destruction throughout Afghanistan, and has also been cited by scholars as a significant factor that contributed to the dissolution of the Soviet Union, formally ending the Cold War. The war began after the Soviets, under the command of Leonid Brezhnev, launched an invasion of Afghanistan to support the local pro-Soviet government that had been installed during Operation Storm-333. Numerous sanctions and embargoes were imposed on the Soviet Union by the international community in response. Soviet troops occupied Afghanistan's major cities and all main arteries of communication, whereas the mujahideen waged guerrilla warfare in small groups across the 80% of the country that was not subject to uncontested Soviet control—almost exclusively comprising the rugged, mountainous terrain of the countryside. In addition to laying millions of landmines across Afghanistan, the Soviets used their aerial power to deal harshly with both rebels and civilians, levelling villages to deny safe haven to the mujahideen and destroying vital irrigation ditches.