South Korea's military believes North Korea has reached the point where it can conduct a surprise nuclear test at any moment.
 
In a briefing on Tuesday, Defense Ministry Spokesman Kim Min-seok said the ministry and the Joint Chiefs of Staff formed a crisis management task force on Monday morning. He said it will regard moves within North Korea pointing to a possible nuclear test.
 
Spokesman Kim said multiple activities are being detected at the Punggye-ri nuclear site in Kilju County, North Hamgyong Province, but added the moves could also be a concealing tactic.
 
Citing bilateral intelligence matters with the U.S., Kim said it's difficult to discuss the more impending signs of a nuclear test, such as the filling of tunnels, the installment of seismic wave measuring devices and the connection of communication cables between devices and ground control stations.
 
South Korean and U.S. intelligence authorities are believed to have detected movements in North Korea since last week, including increased vehicle traffic and shielding screens set up at the nuclear site.