
The robber entered the Chase branch at 600 North Dearborn St. at about 9 a.m., handed a teller a note announcing the robbery and threatened harm if her demands weren't met, according to an FBI spokeswoman.
She got an undisclosed amount of money and fled on foot.
She was described as white, between 25 and 30 and about 5-foot-7. She had brown hair and sported a ponytail. She wore sunglasses, a black sweatshirt, black pants, a baseball-type cap and carried a black purse.
She did not display a weapon.
Of the 59 bank robberies in the Chicago area this year, this is the second committed by a woman, said FBI spokeswoman Cynthia Yates. The first was dressed as a nun in a Palos Heights robbery, and she has been captured.
"The number of female robbers is rising," Yates said. "The numbers nationally are up 7 to 8 percent this year."
Anyone with information is asked to call the FBI at 312-421-6700.