A magnitude-3.4 earthquake has been detected in North Korea.
The earthquake occurred about 50km from a nuclear test site, monitors say. Previous quakes have occurred during weapons’ tests.
Chinese seismologists said it was a “suspected explosion”. But South Korea says that it could be a natural quake not caused by a nuclear test.
North Korea carried out a massive nuclear test on 3 September which has been widely condemned at the UN.
The size of Saturday’s tremor is smaller than that usually detected when North Korea has tested weapons.
After the last test, initial reports from the US Geological Survey put the tremor at magnitude 5.6 with a depth of 10km (six miles) but this was later upgraded to magnitude 6.3 at 0km.
The latest quake was recorded at a depth of 0km in North Hamgyong province, home to the Punggye-ri nuclear site, South Korea’s meteorological agency says.
It said it believed the quake was natural because the specific soundwaves generated by artificial earthquakes were not detected, Reuters news agency reports.
Analysts from the Comprehensive Nuclear Test Ban Treaty Organization are examining the “unusual seismic activity of a much smaller magnitude” in North Korea, executive secretary Lassina Zerbo tweeted.
He said the quake occurred “about 50km from prior tests”.
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