Police said the man first hit the Orange County Credit Union on South Harbor Boulevard in Fullerton, then the Union Yes Federal Credit Union on West Chapman Avenue in Orange, then the U.S. Bank on Beach Boulevard in Buena Park.
The three robberies were all conducted in a 90-minute span starting at 9:30 a.m. Friday.
The suspect is described by witnesses as a black man in his 30s, weighing over 200 pounds with a muscular build. He was seen wearing a white polo-style shirt with blue jeans and may have been carrying a black backpack.
In each robbery, he approached the teller and passed a note demanding large bills in 100s and 50s. No weapon was seen during the robberies.
If you recognize the man in the surveillance photos, you're urged to call the FBI at (888) CANT-HIDE or (888) 226-8443.