has since been used by Southern missionaries attempting to evangelize the North. By the late 1980s, it became apparent that Christians were active in the governmental elite. In those years, three new churches, two Protestant and one Catholic, were opened in Pyongyang. The number of churchgoing North Korean Christians more than doubled between the 1980s and the early 2000s, with a total of thirty ministers and 300 church officials. Proselytizing is prohibited based on the theory that it opens North Korea to impermissible foreign influence and the increase in churchgoing Christians is attributable to an active search for North Koreans who previously practiced privately or in small home congregations. Other signs of the regime's changing attitude towards Christianity included holding the "International Seminar of Christians of the North and South for the Peace and Reunification of Korea" in Switzerland in 1988, allowing papal representatives to attend the opening of the Changchung Cathedral of Pyongyang in that same year, and sending two North Korean novice priests to study in Rome. A Protestant seminary in Pyongyang taught future leaders of the North Korean government. A new association of Roman Catholics was established in June 1988. A North Korean Protestant pastor reported at a 1989 meeting of the National Council of Churches in Washington that his country had 10,000 Protestants and 1,000 Catholics who worshiped in 500 home churches. Today, the total number of Christians in North Korea is liberally estimated to be no more than somewhere between 12,000 and 15,000. In 1992 and 1994, American evangelist Billy Graham visited North Korea. He met Kim Il-sung, giving him a Bible, and preached at Kim Il-sung University. In 2008, his son Franklin Graham visited the country. In 1991, North Korea invited the Pope to visit. In 2018, the government invited Pope Francis to visit. In late 2018, Metropolitan Hilarion Alfeyev of the Russian Orthodox Church visited North Korea, meeting with officials and leading a service at the Church of the Life-Giving Trinity in Pyongyang. North Korean Christians are officially represented by the Korean Christian Federation, a state-controlled body responsible for contacts with churches and governments abroad. In Pyongyang there are five church buildings: the Catholic Changchung Cathedral, three Protestant churches inaugurated in 1988 in the presence of South Korean church officials, and a Russian Orthodox church consecrated in 2006. The internationally-supported Pyongyang University of Science and Technology, which opened in 2010, operates with a