From The Fortress: The Siege of Przemysl and the Making of Europe’s Bloodlands, by Alexander Watson (Basic Books, 2020), Kindle p. 71:
KUSMANEK’S FIRST TWO tasks at the war’s start were to protect the Fortress from surprise attack and to prepare it for siege. The third, however, was inward-looking: to maintain internal order. Kusmanek possessed formidable powers to fulfill this objective. Galicia fell within the extensive “Area of the Army in the Field” declared on July 31, 1914, in which military commanders were placed above the civilian administration. On August 2, repressive martial law was imposed throughout this area. Unrest or rebellion, high treason, espionage, lèse majesté, and a host of other offenses detrimental to smooth mobilization were henceforth to be tried in military courts. Through the Fortress Command court, over which Kusmanek presided, passed a stream of civilian cases from the surrounding region.
The Fortress Command, like other military and civilian authorities in Galicia, acted preemptively to smash all possible resistance. Lists of potential traitors had been drawn up by district officials in peacetime, and across the province, over 4,000 people were arrested in the first days of war. The Russophile intelligentsia was the primary target, but through paranoia, denunciations, and the cynical exploitation of the emergency by some Polish officials to rid themselves of troublesome local opponents, many Ukrainian nationalists, for whom rule by the Tsar would be a catastrophe, were also taken into a Kafkaesque “preventive detention.” The Greek Catholic Church, to which most Ruthenes adhered, suffered particularly grievously. The similarity of its eastern rites to those of the Russian Orthodox Church, and the fact that a small minority of its priests were Russophile, all fueled suspicion. Its churches around Przemyśl had been built with Russian funds, went one rumor, as landmarks to help orientate an invading army. In the Przemyśl diocese, where 873 clergy had their ministries, more than a third of the priests, 314 altogether, were interned.