culture, Khmer Rouge soldiers were known to destroy records and master tapes containing any Western-influenced music genres, and often forced residents to burn their record collections. The only Cambodian rock records to survive were the few that citizens managed to hide in personal collections, and many of those were damaged to the point at which artist names or song titles had been lost. Therefore, except for fans' personal memories, much of the 1960s–1970s rock music of Cambodia was lost until it was slowly rediscovered starting in the 1990s. Relations between the Khmer Rouge regime and neighboring Vietnam collapsed in late 1978, igniting the Cambodian–Vietnamese War. Vietnam launched a full-scale military invasion of Cambodia in December 1978 and captured Phnom Penh the following month, thus ending the Khmer Rouge regime and the Cambodian genocide. Vietnamese forces sent the Khmer Rouge into exile in Thailand and installed Heng Samrin as the new leader of the restored Cambodia. Residents who had been exiled to farm camps and other Khmer Rouge installations were invited to return to Phnom Penh. Singer Sieng Vannthy, who had survived the genocide, was invited to make an announcement on Cambodia's national radio station that residents were welcome to return to the city. Those who did not return were considered dead, including musicians. Rediscovery After the fall of the Khmer Rouge, surviving Cambodian rock musicians regrouped and attempted to locate missing colleagues. Many musicians contacted Ros Saboeut, older sister of Ros Serey Sothea, to inquire about Sothea's fate. Sothea did not survive the genocide but Saboeut took the opportunity to reunite Cambodia's surviving rock musicians, maintaining a list of contacts. Saboeut's efforts are widely credited with reviving Cambodian popular music in the aftermath of the genocide. According to Youk Chhang, the executive director of the Documentation Center of Cambodia, Saboeut sought to restore Cambodian music as a tribute to her sister, saying "I think she was bound by the legacy of her sister to help." As with all other aspects of Cambodian society and culture, the country's music scene faced a tough but relatively fast recovery. The post-Khmer Rouge government made specific moves to re-establish the country's radio industry, allowing surviving singers and musicians to resume their careers by creating new entertainment content. For example, Drakkar drummer Ouk Sam Art and guitarist Touch Chhatha were able to return to music work at Cambodia's national radio station. The Cambodian music scene