Five youths were charged yesterday with attacking cars that were parked outside a university campus in Thessaloniki, as police investigated whether one of the suspects was involved in clashes during a student rally in Athens two months ago. Police initially detained 15 people after more than 20 youths threw petrol bombs at cars, damaging more than a dozen vehicles, early on Saturday. Five of the detainees were later charged with disturbing the peace, a misdemeanor. But two of the suspects were also charged with possession and the use of explosives, which are criminal offenses. Officers said that one of the pair was part of a group of 49 students who were arrested at the rally in March during which demonstrators set fire to a guardhouse in front of the Tomb of the Unknown Soldier, and was one of the most violent of a series of student protests. The suspect denies taking part in the rally. All five youths are due to face a magistrate tomorrow.