The world governing body, the International Association of Athletics Federations, confirmed on Friday night that five unnamed Jamaican athletes - four men and one woman - failed drug tests carried out at last month's Jamaican Championships in Kingston.According to a source, three of the athletes, two men and the woman, were members of the 4x100 metres relay pools selected for next month's World Championships in Berlin. The other two men were members of the Jamaican 4x400m relay squad.