Three men beat up a father and injured his wife and six-year-old son on one Berlin train on Saturday night, after being told to quieten down.
The three men attacked the family on a regional train between Münchehofe and Strausberg in east Berlin, police said on Monday afternoon.
The three men, who were in their twenties, were talking loudly while sitting next to the family.
The 29-year-old father asked them to make less noise and they began punching him in the head.
When his wife tried to stop them, she was punched in the chest. Her son was also attacked and both suffered bruises.
The father suffered a cut eye and bruises.
When the train arrived at Strausberg station at 9.10pm, the three men fled.
The family, who are originally from Poland and live in Treptow, were taken to hospital in an ambulance after the train conductor called police.
Police are examining video footage from the train. One of the attackers was wearing a white jacket with a hood and another was wearing a camouflage jacket.
Anyone with information should call police on 030 29777 90.
The same night another man in Berlin was taken to hospital with a fractured skill and life-threatening injuries after an argument on the U-Bahn.
Three men were travelling of the U7 line at Siemensstadt, west Berlin, towards Rathaus Spandau when two of them got into an argument.
One of the men hit his acquaintance with his fist in the face and he fell to the floor. The brawl then continued until one witness pulled the emergency brake. The train stopped at Rohrdamm station and the instigator fled, while a witness called emergency services.
The 39-year-old was taken to hospital with a fractured skull.
The third man did not take part in the fight, but also fled with the aggressor.
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