FBI agents have still not been granted permission to visit the consulate building where the American ambassador to Libya was killed, three weeks after the attack by militants in the eastern city of Benghazi. An FBI team was dispatched to Libya within days of the attack, in which three other Americans died. But they have been forced to remain in Tripoli as American and Libyan officials argue over the terms under which the two sides will co-operate in the investigation. The consulate building itself and the accommodation annexe which also came under attack have been left largely unsecured. "We are...