Ethiopian Prime Minister Meles Zenawi on Wednesday (February 1) said rights groups' allegations of widespread abuse of political opponents had no basis in fact and were the result of "sloppy" reporting. London-based Amnesty International said earlier in the day that Ethiopia had arrested thousands of students from the Oromo ethnic group in a crackdown following anti-government demonstrations since November over a disputed election. The whereabouts of many of the detainees were not known, the group said. "Some detainees have been released, but others are being held in locations where torture has frequently been reported," Amnesty added in an urgent appeal. But Meles, in an interview with Reuters, scoffed at the Amnesty report as based on second-hand, biased information.