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.

The source said North Korean military personnel with protective suits responded to the scene soon after the explosion and removed material only from the Syrians' section of the train.

The technicians were from the Syrian technical research center called Centre d'Etudes et de Recherche Scientific (CERS). Although CERS was established to promote science and technology development, it has been viewed as a major player in Syria's weapons of mass destruction development program.

The source said it was not known whether the cargo was the source of the explosion or whether it had exploded following a separate explosion on another section of the train.

As many as 10 Syrians and accompanying North Koreans were killed, according to the report. The bodies of the Syrians were taken home on May 1 by a Syrian aircraft, which had come to Pyongyang to deliver aid supplies.

The Syrians and North Koreans who transported the victimrs were also reportedly wearing protective suits similar to those worn by the North Korean military figures who arrived on the scene immediately after the accident, the source said.

The United States and other countries have expressed concern that Syrian and North Korea are developoing Scud-D missiles, as well as chemical and biological weapons.

Concerning the cause of the explosion incident, the DPRK has explained that a train carrying fertilizer containing ammonium nitrate and a railroad tank carrying petroleum were being shunted, and, in the process, came into contact with electrical wires, due to carelessness.