The department said the man entered the Heritage Community Credit Union, 10339 Folsom Blvd., at about 10:30 a.m. Thursday. After waiting in line, he approached a teller and presented the credit union employee with a note demanding cash.
After the man was given the money, he fled on foot from the credit union with the cash in a white, cloth bag.
He was described as a black man in his 30s, about 6 feet 5 inches tall with a muscular build. Between his eyebrows, deputies said, was either a birthmark or tattoo on his forehead.
He also had a mustache and facial hair on his chin. He was dressed in a black, hooded sweatshirt and black jeans.
Anyone who can identify the man is asked to contact the robbery bureau at (916) 874-5115.