Three people were injured in central Giessen on Saturday after shots were fired in a betting shop, a police spokesman said.
The individual fled on foot and remains at large following the incident, which occurred shortly after 3 pm (1300 GMT) in the city in central Germany.
Police are searching for the perpetrator.
The public is not thought to be in danger, the police spokesman said earlier.
The shop has been cordoned off and forensic investigators are on site.
No information was available on the severity of the victims’ injuries and further details have not been disclosed as the operation is ongoing.