Seoul: South Korean President Yoon Suk-yeol on Sunday announced a period of national mourning and ordered the lowering of flags over a deadly Seoul stampede during Halloween celebrations that killed at least 151 people, including 19 foreigners, media reports said. At least 151 people were killed and 82 others were injured in a deadly stampede during Halloween celebrations in Seoul’s Itaewon district on Saturday, South Korea’s Yonhap news agency reported citing authorities. A day after the stampede, Yoon in a live address to the nation from the presidential office, said, “It’s truly horrific.” He said that this tragedy should never…