A "suspected explosion" near the China-North Korean border caused a small earthquake on Monday, Chinese seismology authorities said, less than an hour after news broke about President Xi Jinping's upcoming trip to Pyongyang.
According to the China Earthquake Networks Center, the 1.3-magnitude earthquake with a zero metre depth occurred at 19:38 PM (1138 GMT) in Hunchun city in northeastern Jilin province.
It was unclear what caused the explosion.
In the past, nuclear tests by Pyongyang have caused tremors and mini quakes around the northern border China shares with North Korea.
In September 2017, a test conducted at North Korea's nuclear site at Punggye-ri under Mount Mantap triggered a 6.3-magnitude earthquake that was felt across China's northern border.
Chinese seismologists later concluded that Pyongyang's main nuclear test site had partially collapsed, rendering it unusable, following the massive bomb blast, which the North claimed was a hydrogen bomb test.
Experts later cast doubt on that claim, with Jeffrey Lewis of the Middlebury Institute of Strategic Studies commenting that there was "no evidence" that it was unusable.
In January 2016, Chinese border residents in northern Jilin province were evacuated from buildings after feeling tremors from a North Korean nuclear test. (AFP)