South Korea's navy fired warning shots at a patrol boat of the Democratic People's Republic of Korea (DPRK) Wednesday after it crossed the disputed inter-Korean maritime border on the Yellow Sea, according to South Korean military.

The DPRK vessel retreated and there were no further hostile exchanges between the two sides, the South Korean Joint Chiefs of Staff (JCS) was quoted by South Korean Yonhap News Agency as saying.

It was first violation of the DPRK vessels of the controversial Northern Limit Line (NLL) since June 15, when the navies of the two countries activated a hot line to prevent accidental military clashes.

The DPRK patrol boat intruded 0.7 mile into southern waters along the NLL shortly before 5 p.m. (0800 GMT). After issuing a warning, a South Korean navy speedboat fired two shots and the DPRK boat returned to its territory 14 minutes later.

Yonhap quoted source at the JCS as saying that the intrusion appeared to be an accident because the DPRK boat was dispelling illegal fishing boats of another country.

Up to now, the DPRK has not accepted the conception of NLL, while South Korea views it the de facto sea border with the DPRK. Navies of the two sides exchanged fire around the NLL in 1999 and 2002, both of which led personnel and material loss of the two sides.

In order to prevent possible conflict along the NLL, general level military officials of the two countries held meetings in May and June to outline joint measures.

They set up the military hotline between their navies in the spirit of the senior level inter-Korean military talks.