Former Olympic middle-distance track and field champion Sebastian Coe, now Lord Coe, said yesterday that the fight against drugs in sport would become much more effective if authorities tried to uncover the sources in the illegal trade of substances and how an athlete came to use them rather than simply punishing the offenders. «It is (the sports authorities) responsibility to look beyond positive tests and to act forensically,» he told an an audience of journalists and sports officials at the headquarters of Athens 2004, the Games organizers. Coe denied there were concerns about Greek athletes using banned substances. «I have not come across excessive concerns in the international sports community,» he said, adding that it was not surprising for a host nation to use «better targeting of resources» to produce more Olympic medals than usual. «We should not read more into it,» Coe said. Lord Coe, who earned two gold and two silver medals in the 1980 and 1984 Olympics, recalled his first international competition, as a junior, at the Karaiskaki Stadium in 1975, and added that his tour of Olympic venues had enhanced his support of a London bid for the 2012 Games.