A South Korean official says South and North Korean naval vessels exchanged gunfire at the western sea border on Tuesday morning.

The official said South Korean naval vessels fired warning shots at 11:28 a.m. when a North Korean patrol boat crossed the Northern Limit Line into South Korean territorial waters, but the North Korean vessel continued on its course and responded with return fire.

The Defense Ministry in Seoul said that no South Korean sailors were hurt, and that it has not received word on whether there were any North Korean casualties. The ministry added that the exchange of gunfire, which occurred nine kilometers east of Daecheong Island, lasted for about two minutes.

The North Korean vessel was half-destroyed when it returned to the North. Smoke was reportedly seen rising from the North Korean vessel.

At the time of the gunfire, there were nine South Korean fishing vessels in the area, but none were damaged and all were safely evacuated.