German police were Tuesday seeking three youths who attacked train passengers in Munich in a case that is expected to further inflame a political controversy over juvenile delinquency, according to DPA. Two male passengers, both 45, asked the boys to turn down loud MP3 players inside the mass-transit train on Sunday. One youth immediately jumped up and punched one of the complainants in the face. The trio chased the two men when they alighted, knocking one to the ground and kicking him, and throwing a brickbat at the other's head. The assailants' race was not known. Police did not disclose the case till Tuesday. The victims suffered bruises, abrasions and cuts. After a similar attack two weeks ago on a retired Munich man who had asked youths to obey a smoking ban in an underground station, right-of-centre German politicians called for non-German attackers to be deported, and demanded boot camps for delinquents. The suspects in the pre-Christmas attack in the Munich train system, who face attempted-murder charges, are a 17-year-old Greek national and a 20-year-old Turkish national.