Rising tensions on the Korean peninsula are jeopardizing a joint industrial project that has served as one of the few remaining symbols of reconciliation between Seoul and Pyongyang.
North Korea has warned the South it will abandon the Kaesong Industrial Complex and turn the border area back into a military zone if Seoul follows through on its pledge to tighten inspections there.
Earlier this week, Seoul's Unification Ministry said it would more closely monitor industrial parts and other cargo shipped into the facility, as a result of expanded U.N. sanctions against Pyongyang following a banned November rocket launch.
North Korean has reacted angrily to the sanctions, promising to launch more missiles and conduct another nuclear test, which is expected to take place in just days.