Seoul: Authorities on Tuesday issued a flood advisory for the Imjin River in a county near the border with North Korea as water levels rose sharply due to heavy downpours, with the reclusive North also releasing water from a dam near the border without any advance warning.

According to Yonhap News Agency, the Han River Flood Control Office issued the warning at 11:40 a.m., shortly after the water level at Imjin Bridge in Yeoncheon County, about 60 kilometers northeast of Seoul, reached 7 meters, rising 0.2 to 0.3 meters every 10 minutes.

The bridge's water level has been on a sharp rise as heavy rainfall pounded the county and North Korea appeared to have released water from a dam near the inter-Korean border without giving prior notice. The environment ministry said late Monday that satellite imagery confirmed the release of water from the Hwanggang Dam on the upper reaches of the Imjin River.

The water level at Pilseung Bridge, the northernmost point of the Imjin River in South Korea, measured 8.1 meters at 11:40 a.m., surpassing the 7.5-meter threshold for the second-highest level of the river's flood management scheme, according to the flood control office.

The office and the county have sent mobile safety warnings to residents and visitors in the area, urging them to stay away from rivers and evacuate to safe locations.