(Portland, OR)  --  Three suspects are in custody and police are searching for a fourth following an hours-long manhunt that shut down several blocks in southeast Portland.  Police responded to the area of Southeast 104th Avenue and Mitchell Street yesterday afternoon on reports of a suspicious vehicle.  Responding officers say the suspect vehicle sped off when they tried to approach it, but it eventually stopped, at which point four people allegedly got out and fled on foot.  Officers detained one suspect near the car and later tracked down two more suspects after a resident reported seeing them run through her backyard with a gun.