SEOUL • A Chinese fishing trawler caught illegally fishing in South Korean waters tried to make a dash for freedom across the Northern Limit Line (NLL) into North Korean waters on Saturday, even though 14 South Korean coast guard personnel were on board.

Coast guard officials in Incheon said the 50-tonne vessel was initially detected on Saturday about 50km off the coast of Yeonpyeong Island, reported the Chosun Ilbo news daily.

The vessel had attempted to flee when the coast guard began its pursuit and the vessel, with a seven-member crew, was boarded around 5km south of the maritime border between the two Koreas.

But despite an order to stop, the crew shut themselves in the wheelhouse of the vessel and made a desperate attempt to escape by continuing for another kilometre.

The coast guard finally managed to bring the boat to a halt by covering up the engine's air vents, causing it to stop.

Despite an order to stop, the crew shut themselves in the wheelhouse of the vessel and made a desperate attempt to escape... The coast guard finally managed to bring the boat to a halt by covering up the engine's air vents, causing it to stop.

"If we'd failed to stop the Chinese trawler, we would have had to give up the chase before it crossed the NLL," one coast guard officer said.

In a separate incident, another Chinese vessel that was fishing illegally in the mouth of the Han River - an area deemed neutral territory by South and North Korea - dodged the South Korean security forces by fleeing to the North Korean coast, Chosun Ilbo reported.

The military said the trawler was ignored by North Korean forces and alleged that they had been paid off.

North Korea's military is known to sell fishing rights on the Yellow Sea to Chinese fishing boats. However, the area in the mouth of the Han River does not fall under North Korea's jurisdiction.

Last Friday, South Korea and the United Nations Command, which overseas the Korean War armistice, announced a joint operation to keep Chinese fishing vessels from operating illegally off the west coast.