PORTLAND, Ore. -- FBI agents said that they suspect a North Portland bank robbery on Friday may be the fifth for a robber they've titled the "Benjamins Bandit."

The robber entered the United Advantage Credit Union at 1430 North Killingsworth Street in Portland at about 11:15 a.m. and demanded cash, FBI agents said. The man earned his nickname because in each of the robberies he's been connected to he demands only $100 bills.

The robber has never threatened tellers with a weapon and no one has been injured in any of the robberies, FBI agents said.

The Benjamins Bandit is also suspected in four other robberies:

June 12 at 2:15 p.m. -- Bank of the West, 905 NE Halsey, Portland

May 30 at 3 p.m. -- Wells Fargo Bank, 4233 NE Sandy Blvd., Portland

May 22 at 1 p.m. -- Consolidated Federal Credit Union, 2021 NE Sandy Blvd., Portland

April 16 at 11 a.m. -- Riverview Community Bank, 10401 NE Halsey, Portland

Witnesses describe the robber as a black man in his 30s, about 5 feet 10 inches to 6 feet tall. In each of the robberies the man has worn some kind of baseball cap, sunglasses and the same black leather jacket and diamond-stud earrings.

View Images Of The "Benjamins Bandit"

Anyone with information about the robberies can call the FBI at 503-224-4181 24 hours a day.