The robbery took place at the Fifth Third Bank at LaSalle and Madison streets in the Loop Monday morning.
An FBI spokesperson said agents are on the scene with Chicago police.
SEE ALSO: Chicago police issue warning for string of armed robberies downtown, on North Side
Officials did not immediately provide any additional information about how much money was taken, if anyone was injured, who was involved in the robbery or if a weapon was involved.
Chicago police were on the scene just before 11 a.m.
This is a developing story; check back with ABC7 Chicago for updates.
INTERACTIVE SAFETY TRACKER | Track crime and safety in your neighborhood