<p><br /> Five people have been arrested in the relation to a stabbing of a 15-year-old boy in South London.<br /> </p><p><br /> Zac Olumegbon was stabbed to death in a planned attack by suspected rival gang members as he arrived at school.<br /> </p><p><br /> Olumegbon, from Brixton Hill, south London, was ambushed by four young men at the gates of Park Campus School in nearby West Norwood.<br /> </p><p><br /> A second teenager, believed to be 14 years old, was also stabbed in the arm during the incident. A local shopkeeper described how Zac fell into the arms of a teacher after the attack.<br /> </p><p><br /> Police believe four black males arrived in a car before the attack and a confrontation took place outside the school involving the two victims and the suspects.<br /> </p><p><br /> Three of those being questioned by murder squad detectives after the incident are believed to be teenagers.<br /> </p><p><br /> Zac was the 13th teenager to be killed in the capital this year as senior officers pull out all the stops to keep a lid on violence among young people.<br /> </p>
