KATHMANDU — Nepal does not need foreign assistance for search-and-rescue operations following the devastating flash flood that swept through several towns on Wednesday, its foreign ministry said, despite offers from several countries with nationals missing. The flood tore through areas including Rasuwa district near the Chinese border, levelling entire towns, damaging hydropower plants and killing close to 500 people. Hundreds of foreign nationals are still missing, including from South Korea, which said it has already sent a response team to Nepal and will also dispatch a disaster relief team. But Nepal's foreign ministry said on Friday that it was managing the rescue efforts itself. "The offer for help is natural. Our security agencies are doing the search-and-rescue operation. For now we don’t require such help," Lok Bahadur Chhetri, spokesperson for the foreign ministry, said on Friday. The Kathmandu Post reported that India, China, the United States, Britain, Japan, South Korea, Sri Lanka and Bangladesh had asked the government to allow their search-and-rescue teams to assist in