 Complete the following phrase:  In 1909, upon his return to the Caucasus, Nzhdeh was arrested by the Russian authorities and spent three years in prison. In 1912, together with General Andranik Ozanian, he joined a battalion of ethnic Armenians within the Macedonian-Adrianopolitan Volunteer Corps of the Bulgarian army to fight against the Ottoman Empire in the Balkan wars, partaking in the campaigns to seize Thrace and Macedonia. During the 