The suspect got away with an undisclosed amount of cash from the Horizon Bank on Franklin Street back on Sept. 30, police said.
It happened about 10:30 a.m. at the bank, located at 515 Franklin St., according to Michigan City police.
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Anyone with information is asked to contact Lt. Anna Painter at (219) 874-3221, extension 1077, or at apainter@emichigancity.com.
The Michigan City Police Department can also be contacted via Facebook Messenger, through a crime tip hotline number of 219-873-1488 or the WeTip Hotline for General Crime (800) 78-CRIME.
Those who submit information could possibly receive a reward upon an arrest and conviction. All WeTip call information is sent directly to the LaPorte County Prosecutor's Office.