A North Korean man has defected to a South Korean western border island on Friday and is currently under investigation by authorities, a military official said.

“An unarmed North Korean man arrived in Gyodong Island earlier in the day,” a military official said. “He was found by residents at around 3:40 a.m.”

The 46-year-old man knocked on the door of an island resident‘s home, saying he came from the North, the official said.

He was subsequently reported to military officials who took custody of him, the official said, saying he is currently being questioned by the officials over his motivation for defecting.

Located in the northernmost part of the Yellow Sea off the country’s west coast, the Gyodong Island lies close to the de-facto maritime border, the so-called Northern Limit Line.

The strategically important island is situated only 20 kilometers south of the 38th parallel that roughly divides the two Koreas and is 50 kilometers east of the sites of three major North Korean offshore provocations in the last decade. 

Though Marines are stationed on the island with a population of 5,000, some of its coastal areas are left open without barbed-wire fence to allow for fishing by the residents.

In September of last year, a North Korean man sneaked into South Korea across the border by holding on to a log that was swept away in flood waters spawned by typhoons. (Yonhap News)