SEOUL, South Korea (AP) -- North Korea fired into disputed waters near a South Korean warship Thursday, a Joint Chiefs of Staff officer said, in the latest sign of tension rising between the bitter rivals in recent weeks.
The officer said North Korea fired artillery toward a South Korean navy ship engaged in a routine patrol mission near the countries' disputed maritime boundary in the Yellow Sea. The South Korean ship was not hit, said the officer, who spoke on condition of anonymity because of office rules.
The official could not confirm a report from Yonhap news agency that South Korea's military returned fire at waters near a North Korean warship. South Korean television network YTN said South Korea fired two rounds of artillery shells at the North, but other details were unknown, including whether artillery was fired from sea or land.
YTN reported that residents on the frontline Yeonpyeong Island were being evacuated. In 2010, North Korea fired artillery at the island, killing two civilians and two marines.
Both Koreas regularly conduct artillery drills in the disputed waters.
North Korea has in recent weeks conducted a string of artillery drills and missile tests and has unleashed a torrent of racist and sexist rhetoric at the leaders of the U.S. and South Korea.
On Tuesday, South Korean navy ships fired warning shots to repel three North Korean warships that briefly violated the disputed sea boundary. On Wednesday, North Korea's military had vowed to retaliate.
North Korean military ships and fishing boats have routinely intruded into South Korean-controlled waters that the North doesn't recognize. The Yellow Sea boundary was unilaterally drawn by the U.S.-led U.N. Command at the end of the 1950-53 Korean War.