SEOUL, South Korea — North Korea on Saturday fired about 10 ballistic missiles toward the eastern sea, South Korea's military said, staging its own show of force as the rival South conducts a joint military exercise with the United States. South Korea's Joint Chiefs of Staff said the missiles were fired from an area near the North Korean capital of Pyongyang , but didn't immediately say how far they flew. Japan's Defense Ministry said the weapons landed in waters outside the country's exclusive