(Portland, OR)  --  Police are searching for a man accused of carjacking someone at knifepoint in Southeast Portland.  Police say the victim was getting into his car in the parking lot of the Food Depot on East Powell Boulevard last night when the suspect approached him.  The victim says the man flashed a knife and demanded his car keys.  The stolen vehicle is described as a white 2001 Nissan Altima with Oregon license plates 1-2-3-E-N-J.