South Korean authorities said Tuesday that its neighbors to the north have stepped up activity at its primary nuclear testing site and could be preparing to conduct a fourth underground test.
“We confirm that we have spotted several activities related to the nuclear test in Punggye-ri in North Korea,” the South Korean Defense Ministry said in a statement reported by CNN. The statement didn’t elaborate on the nature of the activities.
The report comes just a few days before President Obama is set to visit South Korea as part of a White House sweep through Asia. Meanwhile, North Korea had stated last month that it won’t rule out “a new form of a nuclear test,” without explaining further, CNN reported.
In response to the activity, South Korea’s military has started monitoring the site as best possible, looking for more signs of activity. The site is located in the northeastern part of North Korea.
Pyongyang has conducted at least three other underground tests involving plutonium, the latest of which took place in February 2013. All three previous tests brought on international outcry.