(Portland, OR) -- Police are investigating a stabbing death in downtown Portland. Authorities say the victim, who's believed to have been in his 30s or 40s, was found dead around 2:25 this morning at the corner of Southwest 4th Avenue and Madison Street. Police closed off the streets around Terry Schrunk Plaza, Chapman, and Lownsdale squares during the on-scene investigation. Anyone who has information on the stabbing is asked to call the Police Bureau at 503-823-3333.