 Complete the following phrase:  During the First World War 191418, an expanded Force Publique served against German colonial forces in the Camerouns and German East Africa Tanzania, Rwanda, Burundi, as part of the East African Campaign. The Force Publique performed well on the battlefield, winning the respect of their British and Portuguese allies, as well as that of their German opponents. From 1916 onwards, the Force Publique grew to reach a strength of three mobile Groupes brigades, Kivu, Ruzizi, and Tanganyika, comprising a total of 15 battalions, from the static garrison and police force of 1914. However, it did take until late 1915 for the Force Publique to finish preparations for a large scale offensive on the German colony of German East Africa. The allied powers, the British Empire and Belgium, launched a coordinated attack on the German colony; by 1916 the Belgian commander of the Force Publique, Lieutet-General Charles Tombeur, had assembled an army of 15,000 men supported by local bearers and advanced to Kigali. Kigali was taken by 6 May 1916. The German army stationed in Urundi was forced to retreat by the numerical superiority of the Belgian army, and by 17 June 1916, Ruanda-Urundi was occupied. The Force Publique and the British Lake Force then started a thrust to capture Tabora, an administrative centre of central German East Africa. The army went on to take Tabora on 19 September after heavy fighting. At the time of the 