THIS IS INTERESTING, if true:

Syrian technicians accompanying unknown equipment were killed in the train explosion in North Korea on April 22, according to a report in a Japanese newspaper.

A military specialist on Korean affairs revealed that the Syrian technicians were killed in the explosion in Ryongchon in the northwestern part of the country, according to the Sankei Shimbun. The specialist said the Syrians were accompanying “large equipment” and that the damage from the explosion was greatest in the portion of the train they occupied.

Hmm.

UPDATE: Hmm, again:

TOKYO — Japan’s Kyodo News, citing numerous diplomatic sources in Vienna, reported Saturday that the force of April 22’s train explosion at the North’s Ryonchon Station was about that of an earthquake measuring 3.6 on the Richter scale, which would have required about 800 tons of TNT — about eight times that officially announced by North Korea. . . .

The CTBTO feels that the cause of the explosion may differ from the North’s explanation, and noted the explosion might have been caused by highly-explosive materials like military-use fuel going off. Officials at the CTBTO plan to look into the causes of the accident.

The CTBTO said the explosion at Ryongchon was observed using seismological observation stations in Korea, Japan, the United States and Russia. The stations were built to detect nuclear tests.

More than meets the eye, or even the seismograph, here, I think.