Bulgarian authorities have done everything that was necessary, Bulgarian Prime Minister Boyko Borissov said, speaking about reports that Chechen Ahmed Chataev, said to be one of the organizers of the recent terrorist attack in Istanbul, was arrested in Bulgaria while attempting to enter Turkey in 2011. Chataev was later released by the court in the city of Haskovo. "The services had detained him and done their job properly," Borissov said. "I do not want to comment on court decisions because they are guided by conventions and international agreements, so if they wanted to give answers, the society would be satisfied," he added.