The manhunt began after the man, who was not in a uniform, crossed the heavily fortified border late on Tuesday.
South Korea’s Joint Chiefs of Staff (JCS) said on Wednesday a North Korean man who crossed the heavily fortified border near the northeastern county of Goseong had been captured and was in custody.
A manhunt had been under way since late on Tuesday when the person was spotted on surveillance equipment crossing into South Korea, Yonhap news agency reported.
“Our military safely captured the man at around 9.50am (00:50 GMT),” the JCS said in a statement. “In coordination with related authorities, we will carry out investigation into the man, including how he crossed the border and if he has the intention to defect to the South.
“No unusual moves by the North Korean military have been detected,” the military added.
Troops had been placed on the “Jindogae” alert, which is issued to cope with a possible intrusion of armed fighters from North Korea, as soon as the man was spotted crossing barbed wire fences installed along the border on Tuesday night.
The man was not wearing a uniform, Yonhap cited officials as saying, but did not reveal whether he was a civilian or a member of the military.
In September, a South Korean fisheries official was shot dead by North Korean troops after he was reported missing while on duty near the island of Yeonpyeong close to the two Koreas sea border.
The killing sparked outrage in the South and drew a rare apology from North Korea’s leader Kim Jong Un.