Tensions rise as North and South Korea exchange artillery fire

By Ju-min Park and Tony Munroe SEOUL (Reuters) - South Korea fired dozens of artillery rounds toward North Korea on Thursday after the North shelled across the border to protest against anti-Pyongyang propaganda broadcasts by Seoul - the first exchange of fire in 10 months. North Korea did not return fire but warned Seoul in a letter that it would take military action if the South did not stop the loudspeaker broadcasts along the border within 48 hours, the South's Defense Ministry said.