Police said the suspect entered the Riverfront Federal Credit Union at 733 Lancaster Ave. just after 9 a.m.
He took out a handgun and approached the teller demanding cash, authorities said. The robber then fled northwest toward the Oakbrook Homes public housing community, officials added. It's not clear how much money was stolen from the bank.
The suspect is described as a 6-foot-tall black man wearing a red zip-up jacket with a hood, black pants, and a black surgical face mask.
To submit a tip, call the Reading Police Department at 610-655-6116, or call the Berks County Crime Alerts tipline anonymously at 1-877-373-9913.
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