SEOUL (Reuters) - High-ranking military officials from North and South Korea met secretly on Wednesday to discuss recent border altercations that involved gun fire, a South Korean opposition lawmaker and news reports said. North Korea's military fired shots on Friday aiming at balloons sent by a private activist group from the South carrying leaflets with messages critical of North Korean leader Kim Jong Un, with some of the bullets landing in the South. South Korea's military fired back in the incident that did not escalate or result in casualties. ...