AlQa'dah 5, 1433, Sep 21, 2012, SPA -- A South Korean official said the South's navy has fired warning shots toward North Korean fishing boats that crossed a disputed maritime boundary between the rivals, according to AP. An official with South Korea's Joint Chiefs of Staff says that no North Korean navy ships were involved in Friday's incident and the South Korean shots didn't hit the fishing boats. The official says the North Korean boats retreated after the shots were fired. The official spoke on condition of anonymity, citing official policy. Violence often erupts in the seafood rich waters claimed by both countries. Boats routinely jostle for position during crab-catching season, and three deadly naval clashes since 1999 have taken a few dozen lives.