(CBS) — A woman who robbed a BMO Harris bank in north suburban Wilmette Tuesday is also suspected of robbing another bank in nearby Skokie last week.

Authorities said the woman robbed the Wilmette branch, located at 1701 Sheridan Road, about 11:48 a.m. Tuesday.

Police responding to a hold-up alarm were told that the woman came up to a teller and demanded money, implying that she had a gun but not displaying it.

The teller gave her an unknown amount of currency, and the woman left the bank. She was last seen running north on Sheridan.

About 2:15 p.m. on Oct. 7, the PNC bank at 5033 Dempster St. in Skokie, was robbed by the same suspect, according to the FBI.

The teller handed over an undisclosed amount of money before the suspect left the bank. She was last seen heading southbound on Leclaire Avenue from Dempster, police said.

The same woman is believed to have robbed both branches, according to the FBI.

She was decribed as a black woman in her 20s, between 5-foot-2 and 5-foot-4, according to the FBI. She was wearing a gray hooded sweatshirt and white baseball cap.

Anyone with information on the robberies is asked to call the FBI at (312) 421-6700.