A troubled industrial zone
The most tangible signs of disruption are in the Kaesong Industrial Complex, the manufacturing zone on the North Korean side of the border where more than 120 South Korean companies operate.
Last week, the North started blocking South Korean personnel from crossing the border back into the complex. And this week, it said it was pulling out the more than 50,000 North Koreans who work inside the zone and temporarily suspending activities there.
It had blocked the border crossing previously, in 2009, but pulling out the workers was a new step.
As of Wednesday lunchtime, only a few hundred South Koreans remained inside the complex, according to South Korean authorities, down from more than 800 before the North started restricting entry.
Also on Wednesday, South Korea accused the North of carrying out a wave of cyberattacks that paralyzed the networks of major South Korean banks and broadcasters last month. It is the first time that Seoul has formally pointed the finger at Pyongyang for the hacking, which affected more than 48,000 computers.