(Portland, OR)  --  A man is facing possible charges after allegedly slamming his car into a government vehicle.  Police arrested 28-year-old Troy Lynn Harrison yesterday for the crash near Southeast 82nd Avenue and Division Street.  Police say officers had tried to pull Harrison over for a traffic stop inside a parking lot when he sped off, hitting a second patrol car.  The sergeant inside the patrol car was hospitalized with non-life threatening injuries.