About 50 people were apparently in cardiac arrest Saturday night as huge crowds stampeded during Halloween festivities in Seoul, the South Korean government said.Fire authorities were administrating CPR to the victims after the disaster occurred in the nightlife district of Itaewon in the capital, Yonhap News Agency reported.President Yoon Suk Yeol instructed government officials to swiftly administer first aid and treat the victims.A total of 142 firefighting vehicles were mobilized to the scene, Yonhap said."