CNN reports that the magnitude 4.9 disturbance happened in an area that, according to the U.S. Geological Survey maps, has "little or no history of earthquakes or natural seismic hazards" leading many to believe that North Koreas conducted a nuclear test on Monday.
Chi Heoncheol, an earthquake specialist at the Korea Institute of Geoscience and Mineral Resources tells the Associated Press, "There is a high possibility that North Korea has conducted a nuclear test."
He went on to say that a two similar earthquakes in 2006 and 2009 were detected in the North Korea in 2006 and 2009 when they were conducting nuclear tests.
North Korea's nuclear bomb tests in 2006 (1 kiloton) and 2009 (2 kilotons) were small in comparison to the bomb that the 15-kiloton bomb the U.S. dropped on Hiroshima in 1945, but if this is yet another test, it's certainly raising some eyebrows.
"If confirmed as a nuclear test, this act would constitute a clear threat to international peace and security, and challenges efforts made to strengthen global nuclear disarmament and non-proliferation," Tibor Toth, CTBTO.org
Coincidentally, the seismic activity took place less than 24 hours before President Barack Obama was due to make his State of the Union address and also when several East Asian countries are observing the Lunar New Year holidays.
Was the U.S. informed of the nuclear test that may have been conducted on Feb. 11, 2013? USA Today reports that "Kim Min-seok, a South Korean Defense Ministry spokesman ...told reporters that North Korea informed China and the United States of its plans to conduct a nuclear test."
Read more about Monday's possible nuclear bomb test in North Korea here.