The man, a white male 45-50 years old, entered the bank, displayed a handgun and demanded money from a teller. He made off on foot with an undisclosed amount of cash, police said. No car associated with the holdup was seen by witnesses.
The suspect is described as 6 foot 3 inches to 6 foot 5 inches tall, weighing between 230 and 250 pounds. He is unshaven with a light-colored mustache and short brown hair. He was wearing a light green button up shirt, black pants and black-rimmed glasses.
Witnesses described the man as using a bad French accent to disguise his voice.
Anyone with information is asked to contact the Pleasanton Police Department at 931-5100.