Aug. 5 (UPI) -- A gas explosion in a North Korean city across the China border may have injured dozens of people and killed several others, according to multiple South Korean news services. The explosion occurred about 6:10 p.m. Monday in the city of Hyesan, South Korean news service Daily NK reported Wednesday. The cause of the accident was likely a gas explosion that took place in a multi-family residential building in the Tapsong district of Hyesan. Homes built side by side, referred to as "harmonica housing," were destroyed in a chain reaction of explosions, a North Korea-based source told...