South Korean Defense Ministry says it has increased its surveillance activities and established a task force with the US to deal with any North Korean provocation.
The move follows the execution of North Korean leader Kim Jong Un's uncle-in-law, Jang Song Thaek, widely viewed as North Korea's No. 2 man.
Kim Min-seok is a spokesman for South Korean Defense Ministry.
"The South Korean Defense Ministry as its main measures, first of all, is conducting an increase in the US-South Korean united surveillance platform. Secondly, we have strengthened surveillance and security alert on enemy air, naval and ground areas. And our Defense Ministry and the US Joint Chiefs of Staff are conducting general-level crisis management task forces. The main commanders and staffs are also preparing for contingency situations."
North Korea said on Friday that it had executed Jang Song Thaek on charges of treachery.
It's reported that top South Korean presidential security advisers and government ministers held an unscheduled meeting in Seoul on Friday to discuss Jang's execution and its aftermath.
In related development, South Korea's Unification Ministry says Pyongyang offered on Wednesday to hold another meeting on the Kaesong factory park.
South Korean officials say Seoul has accepted the proposal to hold such talks on Dec. 19th.
The Kaesong joint industrial park is one of the key symbols of cooperation between North and South Korea.
It was re-opened in September after a five-month hiatus amid mounting tensions between the two neighbors.