South Korean authorities on Tuesday upgraded the flood status on the Imjin River (which flows across the inter-Korean border into South Korea) to a full warning after water levels at Imjin Bridge in Yeoncheon County, roughly 60 kilometres northeast of Seoul, surged past 10 metres and continued rising rapidly. Heavy rainfall in the area combined with North Korea's unannounced release of water from the Hwanggang Dam on the river's upper reaches drove the sharp increase, with satellite imagery confirming the discharge. South Korea's unification ministry urged Pyongyang to coordinate on natural disasters "in a responsible manner," recalling a 2009 agreement requiring North Korea to give advance notice of dam releases — an accord reached after an unwarned discharge killed six South Koreans that year.