North Korea has deployed about 20 helicopters, including attack helicopters, at two bases near South Korea's Baeknyeong Island, UPI quoted a government official as saying. The helicopters are upgraded versions of Mi-2s, as well as Mi-4 and Mi-8 troop carriers, and some are armed with machine guns and rockets, Chosun Ilbo reported. Baeknyeong Island is South Korea's northernmost island, just south of the maritime border with North Korea in the West Sea. Since Kim Jong Un assumed power in North Korea last year, Pyongyang has deployed rocket launchers, hydrofoils, Mi-2 helicopters and fighter jets along the western coast and conducted military drills, Chosun Ilbo said.