ELIZABETH FLORES � eflores@startribune.com April 23, 2008 - Maple Plaine, MN - The Minneapolis Police Department Mounted Patrol Unit held a graduation ceremony for 10 of its newest officers.The Minneapolis Police Mounted Patrol Unit adds 10 additional officers to its ranks, bringing the total strength of the unit to 30. The grueling six-week training is challenging both mentally and physically. Of the 10 new officers, only one had previous riding experience. The officers learn everything related to horses and riding from the ground up.