Phran In the late 1970s and early 1980s, Thahan Phran set up a covert special task force to suppress the communist terrorists who insurgency in Thailand and black operation to destroy destroy Khun Sa's heroin factory. The unit was known as the Project control and coordination section 513 and 514 (PCCS513 and 514) (Thai:ชุดควบคุมและประสานงานโครงการ 513 และ 514 (ชค.513 และ ชค.514)), they were trained like special forces. The PCCS513 took on a mission to wipe out communist terrorists all over the country, and was the only unit of Thahan Phran Pak Thong Chai Camp who fought throughout the country and was the Thahan Phran's spearhead unit in the battle during Communist insurgency and Vietnamese border raids in Thailand and disbanded in the 1990s. The PCCS514 took on black operation to destroy Khun Sa's heroin factory in the Burmese side opposite Mae Chan District, Chiang Rai Province, Thailand. After the successful destruction Khun Sa's heroin factory, they took on a mission to counter and destroy Khun Sa's drugs along the Northern Thailand border and disbanded in April 1987. In 1979 the influx of Cambodian refugees into Thailand became a significant political problem and a security issue, especially since thousands of them were Khmer Rouge combatants. Thai Prime Minister Kriangsak Chomanan, a professional soldier who had previously been Supreme Commander of the Royal Thai Army, placed the border districts under martial law and authorized the Joint Operation of the Supreme Command to control and provide security for the refugees. The Supreme Command responded by creating Task Force 80 in February 1980, a special Thahan Phran unit charged with defensive duties, refugee management, and the supply of food and weapons to the anti-Vietnamese resistance factions that Thailand supported, particularly the Khmer Rouge, as well as the Khmer People's National Liberation Front and the Armee Nationale Sihanoukiste or ANS. During its brief existence Task Force 80 was accused of frequent human rights violations until it was dissolved in August 1988. One observer summarized the Task Force 80 experiment thus: "In a country with a dizzying array of different military units, the rangers were among the lowest paid, worst trained, and least disciplined of all Thai soldiers. They were at the bottom of the military status hierarchy: a poorly educated group who could not have made it into the more prestigious units. Indeed, they were regarded in some circles as little better than local thugs in