Seoul, May 19 (ANI): South Korean President Park Geun-hye formally apologized on Monday for the ferry disaster last month that killed about 300 passengers, mostly school children, and said she would break up the coast guard because it had failed in its rescue mission. Park said that the coast guard's rescue duties will be transferred to a national emergency safety agency to be set up and the national police will take over its investigative function. The Sewol, with 476 passengers and crew members on board, capsized and sank in April, killing at least 286 people. Eighteen people remain missing after South Korea's worst civilian maritime disaster in 20 years. Of the passengers, 339 were children and their teachers on a field trip from a high school on the outskirts of Seoul. Only 172 people were rescued, with the rest presumed to have drowned. Park said that the coast guard had not only failed in its search and rescue duty but that, in its current form, it would be unable to prevent another large-scale disaster.