A North Korean soldier was shot by his former comrades while defecting to South Korea across the demilitarized zone, Seoul's Joint Chiefs of Staff said in a statement Monday.
The wounded soldier was evacuated from the site for emergency medical attention, the statement said, after defecting from a North Korean guard post at the Joint Security Area (JSA) on the heavily-guarded border between the two countries.
The soldier is reported to have left the North Korean guard post in front of Panmungak, on the border inside the demilitarized zone (DMZ), and proceeded to move towards Freedom House on the South Korean side.
It's the same border area that was visited by US Secretary of Defense James Mattis less than a month ago.
Monday's defection is the third by a member of the North Korean military this year, following two soldiers who fled to South Korea separately in June.
Prior to 2017, there had only been four military defectors from North Korea over the past five years: one in 2016, one in 2015 and two in 2012.
Robert Kelly, associate professor at the Department of Political Science at Pusan National University, said the prominent defection and the shooting was "genuinely surprising."
"It's fairly unusual, I can't think of the last time (a defector was shot at) ... it certainly adds to the tensions," he said.
The defector is currently in South Korean military custody, according to the statement.
"Our military has raised the alert level in anticipation of North Korean provocation. The military is maintaining a full readiness," the Joint Chiefs of Staff statement said.
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.
US man arrested
In a bizarre twist, Monday's successful defection from North Korea came as an American man was arrested in South Korea apparently attempting to go in the other direction.
According to South Korea's Ministry of Defense, a 58-year-old man from Louisiana entered a controlled area in Yeoncheon County, on the border with North Korea, early Monday morning.
The man was reported to police by local residents and arrested. Officials said the country's intelligence services, police and military were investigating the case.
South Korea's National Intelligence Service (NIS) confirmed a US citizen had attempted to enter North Korea via the DMZ, but would not give any further information.