One suspect is in police hands – an international manhunt is underway for the other.After studying surveillance camera pictures, Belgian detectives are questioning a 16-year-old over the murder of a fellow teenager. The victim was stabbed to death when he refused to hand over his MP3 player. The youth in custody is Polish. His parents reportedly live in Belgium illegally. The other alleged attacker is also believed to be a Pole who is now back in his homeland. And it is this youth who, it is suspected, wielded the knife. For Belgian authorities that poses a problem. A spokesman from the Public Prosecutor’s office said it may be impossible to secure his extradition if he is young enough to be classed as a minor. Joe Van Holsbeeck, 17, was brutally slain during the evening rush-hour at Brussels Central Train Station. Fellow pupils at his school gave their reaction to the latest development. For one boy, news of the suspects’ nationality was shattering. “It really hurts,” he said. “I found out they were Poles and, as I am Polish myself, it gave me a shock.” Initially, it was rumoured the attackers may have been of North African origin – something that heightened racial tension in Belgium. “People should wait before jumping to conclusions,” said another pupil. Sunday saw Belgium’s biggest demonstration since 1996 when people poured onto the streets in honour of those who had suffered at the hands of paedophile Marc Dutroux. This weekend, more than 80,000 marched through Brussels to protest at senseless violence – and to remember one of its victims, teenager Joe Van Holsbeeck.