SEOUL, A wooden boat believed to be from North Korea was found right off the east coast on Friday, but nobody was aboard, the Joint Chiefs of Staff (JCS) said.

The Coast Guard found the small boat some 30 meters away from the shore in the northeastern town of Goseong, Gangwon Province, at around 10:37 a.m., while patrolling the area, the JCS said.

The town is about 20 km from the Northern Limit Line (NLL), the de facto sea border with the North.

The 9.74-meter-long boat did not have an engine, and some fishing nets were found on it. The boat was nearly submerged when the officers first spotted it, the JCS added.

"Though no suspicion of espionage was found so far as the boat bears traces of submersion, we are looking into the case leaving all possibilities open," a JCS officer said.

It is unclear if anybody got off the boat before the Coast Guard found it, though the initial probe indicated few such chances, he said, adding that the boat was hauled to an Army unit in charge of the area for further investigation.

This year alone, a total of 12 North Korean boats have been found stranded south of the NLL, according to the officer.

The incident took place about a month after a wooden boat carrying four North Koreans arrived at the port of Samcheok, Gangwon Province, after crossing the inter-Korean maritime border unchecked.

In the face of mounting criticism over the military's failure in coastal and maritime operations, the defense ministry vowed to take measures to beef up security of the inter-Korean sea border, including the deployment of an additional naval ship, increased patrol flights and the installation of more radars on and offshore.

Source: Yonhap news Agency