A mysterious heat source the South Korean military detected floating down the Imjin River on the North Korean border late Thursday night turned out to be a man seeking freedom.

“The North Korean soldier came down the river with only his head above the water,” Seoul’s Joint Chiefs of Staff (JCS) said in a CNN report, which credited the South Korean Ministry of Defense for the information.

“A South Korean soldier on guard duty first found an unidentified object floating in the river via thermal observation devices, which was later confirmed as a person. The military then took him safely into custody in accordance with due protocol,” a JCS officer said in a Yonhap News Services report. ”The man is an active-duty soldier, and he expressed his desire to defect to the South. Related procedures are underway.”

CNN reported:

Defections of soldiers over the Demilitarized Zone (DMZ) that separates the two Koreas are rare compared to crossings made by civilians over the border between North Korea and China. To cross the heavily patrolled DMZ requires getting across several fences and a dense minefield. The last time a North Korean successfully defected through the area was in December last year when two soldiers crossed the line several weeks apart. The South Korean military said he was discovered about 300 meters from a guard post, which said the defection by river was the first since 2010.

The man, who has yet to be identified, “expressed the intent for defection” South Korean officials said.

Although there are no official statistics on how many people have defected from North Korea, South Korea reports that 32,000 North Koreans have come into the country since 1998, according to CNN, including 1,137 last year.

CNN reported on one dramatic defection in November 2017 captured on security cameras:

The video showed the North Korean soldier Oh Chong Song speeding to the border in his jeep. When the jeep got stuck in a ditch, he abandoned the vehicle to dash across amid a hail of bullets from his former fellow soldiers. He was shot five times and survived after undergoing a series of extensive surgeries in South Korea. The North Korean military has more than 1.2 million active soldiers and a further 7.7 million in reserves. It is one of the largest ground forces in the world.

According to a United Nations report, defecting is a dangerous gamble.

Global News reported:

Illegally leaving North Korea is considered a serious offence under the Criminal Code. People who illegally cross the border are often considered to have committed treason by defection – punishable by a minimum of five years of “reform through labour.” The United Nations also believes that people who are caught fleeing North Korea are subject to torture, inhumane treatment and imprisonment. The UN has also heard some reports of executions.

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