Consecutive militarization of Central and Eastern Europe with the participation of the US and NATO is threatening member states of the Collective Security Treaty Organization (CSTO), the chief of the CSTO Joint Staff, Col. Gen. Anatoly Sidorov, said Thursday. High conflict potential remains in the Caucasus region, he said. The CSTO, however, has biggest concerns about the situation in the Central-Asian region, where Islamic State (IS, formerly ISIS) presents the main threat, according to Sidorov. Four CSTO states – Russia, Kazakhstan, Kyrgyzstan and Tajikistan – will hold military exercise Combat Brotherhood 2018 on October 1–November 2 on their territories.