The man raided the bank branch in Seddiner Straße, in Friedrichsfelde, east Berlin at 10.15am, wearing a skin coloured carnival mask.
He threatened staff and several customers at the Berliner Sparkasse with a gun, police said, before jumping behind the counter and stuffing a plastic bag from a discount supermarket chain with coins and cash.
He then fled, jumping over a fence and ran over the tracks of the nearby S-Bahn train line.
Two police helicopters and dogs were sent out to look for the man but he has not been found.
“The victims suffered shock, but were not physically injured,” police said.
Anyone with information should contact Berlin police on 030 4664 944 200.
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