South Korea has fired machine gun rounds at a North Korean patrol boat that crossed into its waters in the Yellow Sea, the South's military said Sunday, threatening the conciliatory mood created by the second round of family reunions taking place in the North, Yonhap reported.

The South Korean Navy fired five warning shots at the vessel around 3:30 p.m. Saturday after it crossed the de-facto western maritime border between the two Koreas known as the Northern Limit Line by hundreds of meters.

The boat was supposedly cracking down on illegal Chinese fishing boats in waters near South Korea's Yeonpyeong Island, the site of a deadly bombardment by the North in 2010, the military said.

The boat retreated about eight minutes after the shots were fired, with no injuries being reported.

"There was no violent clash during the warning process," a South Korean military official said, asking not to be named.

The North, however, condemned the firing as a "military provocation."

"South Korean belligerents carried out a military provocation against our patrol boat, which was carrying out its duties in our waters," a spokesman for the North's Committee for the Peaceful Reunification of Korea told Pyongyang's state media.

The incident took place as the second round of reunions of families separated by the 1950-53 Korean War is being held in North Korea. The families have been temporarily reunited since Saturday for a three-day event.

Source: MENA