ordered Tanzania to undertake full mobilisation for war. In a few weeks, the Tanzanian army was expanded from less than 40,000 troops to over 150,000, including about 40,000 militiamen as well as members of the police, prison services, and the national service. Fighting in December was mostly limited to "trench warfare" along the border, marked by sporadic clashes and air raids. By early January 1979 all Ugandan troops had been ejected from Kagera. Nyerere decided that Tanzanian forces should occupy southern Uganda as revenge for the devastation wrought by Ugandan troops in his country and in order to incite a rebellion against Ugandan dictator Idi Amin. The Tanzanians launched their offensive in mid-February 1979. Major General David Musuguri was appointed commander of the TPDF's 20th Division and tasked with overseeing the advance into Uganda. They steadily advanced, killing dozens of Ugandan soldiers and destroying large amounts of their materiel. Following the capture of Masaka and Mbarara, the TPDF halted to reorganise. Silas Mayunga was promoted to major general and given charge of a newly formed "Task Force", a unit consisting of the 206th Brigade and the Minziro Brigade, which was to operate semi-autonomously from the 20th Division. While the 20th Division moved out of southeast Uganda and attacked major locations in the country, the Task Force advanced north into western Uganda in the following months, engaging Ugandan troops conducting rearguard defensive actions. The 20th Division captured Kampala on April 11 and overthrew Amin's government. The fall of Kampala marked the first time in the post-colonial history of the continent that an African state seized the capital of another African country. The war ended on June 3, 1979; after Tanzanian forces occupied Uganda's border region with Sudan and Zaire. Some Western military analysts attributed Tanzania's victory to the collapse of the Uganda Army, arguing that the TPDF would have been defeated by most other African armies. Others felt that the TPDF's success indicated substantial improvements in African military capabilities over the previous years. When the TPDF began returning en masse to Tanzania, only a small number of soldiers were demobilised, contrary to public expectations. Military commanders then began making accommodations to render the wartime expansions of the army permanent, creating new units and divisional headquarters. Some in the military hierarchy expressed disapproval in light of Tanzania's bleak financial situation, and the country's depressed economy eventually forced the TPDF to disband many