a Pohang-class corvette was sunk by a North Korean torpedo, resulting in death of 46 sailors near Baengnyeong Island, in the vicinity of the Northern Limit Line (NLL). Present: 2010s In preparation for an ocean-going navy, the ROK Navy established a task force called Maritime Task Flotilla Seven in February 2010. The task force is responsible for the defense of South Korea against sea-borne threats and protection of its sea lines of communication. Since 2009, a Chungmugong Yi Sunshin-class destroyer from the task force is being deployed as the Escort Task Group (Cheonghae) in response to piracy off the coast of Somalia. On January 21, 2011, naval commandos of the task group carried out an operation, and succeeded in rescuing the crew of the hijacked MV Samho Jewelry. As a humanitarian operation, the unit was dispatched to evacuate South Koreans and foreign nationals from war-torn Libya in 2011 and 2014. In December 2013, as part of the ROK Joint Support Group for the Philippines (the Araw unit), ROKS Birobong (LST 682), ROKS Seonginbong (LST 685), and Marines were deployed in humanitarian response to Typhoon Haiyan. In February 2016, the ROK Navy completed a new naval base on the southern coast of Jeju Island for basing the Maritime Task Flotilla and a submarine squadron, in order to strengthen its control over the seas around the Korean Peninsula and to protect the sea lines of communication. It is also known as Jeju Civilian-Military Complex Port because the Jeju Naval Base is designed to be jointly used by military and civilians. In order to support ocean-going operations, the ROK Navy commissioned the 10,000-ton logistics support ship, ROKS Soyang (AOE 51), and launched the first locally designed 3,000-ton submarine, Dosan Ahn Changho (SS 083) in September 2018. The ROK Navy continued shipbuilding programs to upgrade the fleet with local shipbuilders: In order to replace the aging Pohang-class corvettes and Ulsan-class frigates, and to take over multi-role operations such as coast patrol and anti-submarine warfare, the ROK Navy commissioned six 2,300-ton Incheon-class frigates between 2013 and 2016, and the lead ship (FFG 818) of the 2,800-ton Daegu-class frigates in March 2018. Two ex-USN Edenton-class salvage and rescue ships were replaced with two locally built 3500-ton Tongyeong-class salvage and rescue ships between 2014 and 2016. The Navy commissioned a 3,000-ton minelayer, ROKS Nampo (MLS 570) in June 2017. The lead ship of the PKX-B fast rocket