North Korean soldiers briefly crossed the heavily-fortified military demarcation line with South Korea in the second such incident between the two hostile countries in less than two weeks, Seoul said on Tuesday. After South Korean border patrols fired warning shots, the North Korean soldiers immediately retreated across the border again, said the Joint Chiefs of Staff in Seoul. It comes after South Korea reported a similar incident last week said to have occurred on June 9. As in that earlier incident, the group of North Korean soldiers, comprising around 20 to 30 forces, carried construction …