Jan. 29 (UPI) -- A 2.5-magnitude earthquake was detected in an area near North Korea's Punggye-ri nuclear test site, according to South Korea's meteorological agency on Wednesday.
The tremor occurred on Wednesday at 9:33 a.m. local time in an area near Kilju, North Hamgyong Province, the agency said.
The minor earthquake is believed to be the result, or the aftermath, of North Korea's sixth nuclear test, which occurred in September 2017, Seoul said.
Experts have previously said North Korea's sixth test may have involved a bomb that released the same energy as 108 kilotons of TNT. In 2017, they had also warned of a major environmental disaster as a result of the explosion, or a mountain collapse.
On Wednesday, Seoul's weather agency described the tremor as a "natural earthquake," and said the quake occurred in an area less than two miles from the nuclear test site.
Punggye-ri was also the site of Pyongyang's first nuclear test in 2006. The tunnel used for the test has since collapsed, South Korean news service News 1 reported.
In May 2018, North Korea invited foreign journalists to witness the detonation of the test site.
Park Han-ki, chairman of South Korea's joint chiefs of staff, has said the detonation does not mean the site couldn't be restored.
Tunnels 3 and 4 at Punggye-ri can be repaired for use, Park had said during a parliamentary hearing on Jan. 8, according to News 1.
The minor quake is being reported at a time when the United States and South Korea could be discussing missile guidelines.
The Chosun Ilbo reported this week the United States may have agreed to lift caps on South Korean rockets for civilian use, but on Wednesday the presidential Blue House said the report is "impossible to confirm."
U.S.-South Korea missile guidelines date back to 1979 and have been revised three times, in 2001, 2012 and 2017. Rocket thrust is capped at 1 million pounds per second for South Korea, or one-tenth of thrusts allowed in other countries, according to the Chosun.