Mongolia - the Mongolian Navy has a single vessel with a strength of seven men, including one who can swim.[4] Serbia – the Serbian Army operates a river flotilla consisting of: minesweepers, patrol boats, and landing craft on the Danube, Tisza and Sava rivers.[5] Switzerland – The Swiss Armed Forces operate Aquarius-class patrol boats on Lake Geneva, Lake Maggiore, Lake Lucerne, Lake Lugano and Lake Constance. The small vessels are manned by the 10th Motorboat Company of the Engineers Corps. Uzbekistan – operates gunboats and other riverine craft on the Amu Darya under its Frontier Service.[9]