Complex sentence: Arno Mkrtchian, Hrachik Petrossian, A. Mongasagian and Garik Arustamian--were identified and arrested; however, due to certain circumstances, they were later released and handed over to the Armenian authorities.
Split into simpler sentences: Arno Mkrtchian, Hrachik Petrossian, A. Mongasagian and Garik Arustamian--were identified and arrested. They were later released and handed over to the Armenian authorities.