The Chaldean Catholic bishop of Aleppo, Antoine Audo, said on Thursday that up to 30,000 Christians have fled the Syrian city and spoke of his concern about two priests kidnapped weeks ago. Audo, who was in Rome as a representative of the Caritas-Syria charity for a meeting of regional humanitarian organisations, told AFP that the situation in the war-ravaged city was "painful". "I do my work from Damascus. I am in contact with my vicar, my priests, my friends and my relatives. The closure of Aleppo airport and the dangerous road have prevented my return," he said.