Four men, aged 31, 32, 35 and 43, were each shot once, sustaining injuries to their shoulders, legs and upper bodies.
Three of the injured were taken to hospital, but none are in a life-threatening condition.
A 46-year-old man was also injured in the arm in the confrontation in the Bahnhofsviertel district of central Frankfurt.
“The background of the shooting is believed to be a dispute between members of a biker gang,” police said in a statement.
After the shots were fired the gangs sped off in their vehicles. Police said they were unsure how many bikers were involved.
Police added the investigation was moving slowly because of the unwillingness of the victims to talk. No arrests have been made.
A 28-year-old from the biker scene was killed in a shooting in April this year in a park in Frankfurt.
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