Thomason identified the victim as 51-year-old Melvin Murphy, of Oakland.
He said that at about 10:15 p.m., Tuesday patrol officers responded to the 9300 block of Bancroft Avenue to investigate reports of a man down on the street.
An officer spotted a man, later identified as Murphy, suffering from what appeared to be stab wounds, Thomason said. Murphy was transported to a local hospital, where he was pronounced dead.
Thomason said the investigation is ongoing and anyone with information should contact the Oakland Police Department's homicide section at (510) 238-7230.
Oakland police today also identified the victim of a Monday night homicide downtown.
A man was shot at about 9:20 p.m. Monday near a bus shelter in front of the T-Mobile store at 13th Street and Broadway. Thomason identified the victim as 27-year-old Craig Ainsworth, of Oakland.
Police haven't yet identified a third homicide victim, a man who was found shot to death in the 3400 block of Ettie Street in West Oakland at about 10:45 p.m. Monday.