Berlin (dpa / bb) - A young person and his three companions were provisionally arrested in Berlin-Kreuzberg because they had threatened railway safety employees with knife wounds.
The security staff wanted to settle a dispute between two groups at the Warschauer Strasse S-Bahn station on Friday evening, the police said on Saturday.
One of those involved explained to the security staff that they would stab with a knife if they weren't left alone.
The 16-year-old and his three companions, aged 16 to 19, then got on a bus, which was stopped by the alerted police at the Schlesisches Tor.
The quartet was temporarily arrested - although none of them carried a knife with them.
The alleged perpetrator is now being investigated for threat.
His parents did not want to pick him up from the police station.
His companions were also released by the police, but the 19-year-old refused to leave the building.
Instead, he jumped at a police officer and hit him in the chest, it said.
The officer then defended himself with "simple physical violence".
The attacker was injured in the nose.
He refused a supply and filed a complaint against the police officer.
The young man has to answer for attacking law enforcement officers and property damage.
He kicked the glass of a door.
© dpa-infocom, dpa: 210123-99-140428 / 2