The South Korean military fired a warning shot at a North Korean vessel after it crossed a de-facto inter-Korean maritime border off the west coast of the Korean Peninsula.

The South Korean Joint Chiefs of Staff(JCS) said the vessel was first detected in the South on Wednesday morning while drifting northwest of Baeknyeong Island, south of the Northern Limit Line(NLL). 

Nearly four hours of monitoring passed before the ship was confirmed to be a privately-owned commercial vehicle from the North. 

The JCS said that it judged that the vessel’s border-crossing was not intentional but due to weather conditions and engine malfunctions. 

The joint chiefs took measures to let the boat leave, while a South Korean military official added that there was no act of threat from the vessel.