A North Korean soldier has defected to South Korea after crossing the heavily fortified demilitarized zone.

A South Korean defence official said the soldier managed to traverse the DMZ that spans the two nations without any shots being fired, taking advantage of what Yonhap news agency described as thick fog.

It marks the second known defection of a North Korean soldier in recent months. Another man who escaped in November was hit multiple times as North Korean soldiers opened fire, according to the South Korean military, and underwent treatment in the South.

According to the South Korean Ministry of Unification, the number of North Koreans who attempted to defect dropped by more than 10 per cent in the first part of 2017 compared to the year prior.

But that came after an unusually high number the previous year, with the ministry estimating that more than 1,400 people defected from North Korea to the South over the course of 2016.

A ministry official told the Wall Street Journal that some said they were leaving “not just because they are starving, but for a better life, and for freedom and for their children’s education“.

The defections come at a time of soaring tension on the Korean Peninsula. Pyongyang has repeatedly tested intercontinental ballistic missiles and detonated a powerful hydrogen bomb, threatening its neighbours and drawing global condemnation.

Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Show all 6 1 /6 Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb Photos released by North Korea show Kim Jong-un talking to subordinates next to a device thought to be the new thermonuclear weapon. There is no way of independently verifying the pictures STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korea claims it has successfully tested an advanced hydrogen bomb which could be loaded onto an intercontinental ballistic missile AFP/Getty Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A diagram on the wall behind Mr Kim shows a bomb mounted inside a cone STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb North Korean leader Kim Jong-Un (C) attending a photo session with participants of the fourth conference of active secretaries of primary organisations of the youth league of the Korean People's Army (KPA) in Pyongyang STR/AFP/Getty Images Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters Kim Jong-un inspects weapon North Korea says is powerful hydrogen bomb A new stamp issued in commemoration of the successful second test launch of the "Hwasong-14" intercontinental ballistic missile KCNA via Reuters