The Chicago Tribune is reporting board members at Foster Bank, 5225 N. Kedzie, voted on Friday to close the bank until the mold can be cleaned up.
A bank spokesman tells The Chicago Tribune a mold inspector found the contamination.
Employees ABC 7 saw outside the bank Monday were turning customers away and giving them information about the situation.
Bank officials have not yet returned ABC 7's telephone calls
The Kedzie Avenue location of Foster Bank also serves as the bank's headquarters.