Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. December 09, 2011 UN Chief Makes Landmark Visit to Somalia VOA News UN Secretary General, Ban Ki-moon (L) stands next to Somali Prime Minister Abdiweli Mohamed Ali (C Left) after his arrival at Mogadishu's Adan Abulle airport, December 9, 2011. Photo: AFP UN Secretary General, Ban Ki-moon (L) stands next to Somali Prime Minister Abdiweli Mohamed Ali (C Left) after his arrival at Mogadishu's Adan Abulle airport, December 9, 2011. United Nations Secretary General Ban Ki-moon has arrived in Somalia, the first visit by a top UN leader since the collapse of the government two decades ago. Ban met with Somalia's prime minister and officials from the African Union forces. The AU's force in Somalia, AMISOM, is backing the UN-supported Transitional Federal Government (TFG), in the war-torn country that has been without a stable government since 1991. The last president was ousted 20 years ago, and heads of militant groups took over. The U.N. secretary-general's visit is considered a sign that progress is being made in Somalia , as control by Al-Shabab militants decreases, especially in parts of the capital, Mogadishu. Al-Shabab withdrew its fighters from the capital in August after the government launched an offensive with the support of African Union troops. The Islamic group said the move was "tactical" and vowed to return. Since late November, there have been 15 bomb attacks in Mogadishu, and the government has blamed them on al-Shabab. In an interview with VOA on Thursday, a former official with Somalia's National Security Agency said al-Shabab appears to have adopted guerilla tactics to destabilize Mogadishu. Colonel Abdulahi Ali Maow also said al-Shabab appears to have created a unit of more sophisticated fighters, some of whom may have infiltrated pro-government forces. Al-Shabab has been fighting the AU forces in an effort to impose a strict Islamic law in Somalia. Some information for this report was provided by AP, AFP and Reuters. .