By Soo-hyang Choi, Daewoung Kim and Hongji Kim SEOUL (Reuters) -At least 149 people were killed in a crush when a huge crowd celebrating Halloween surged into an alley in a nightlife area of the South Korean capital Seoul on Saturday night, emergency officials said. A further 150 people were injured in the melee in Seoul’s Itaewon district, Choi Sung-beom, head of the Yongsan Fire Station, said in a briefing at the scene. Many of the injured were in serious condition and receiving emergency treatment, the officials said. It was the first Halloween event in Seoul in three years after the countr…