North Korean experts discussed how to load chemical weapons onto missiles when they met with officials in Syria during a secret visit to the country earlier this month, a Japanese newspaper said Monday. Damascus invited the experts for their advice as part of Syria's drive to develop its short-range "Scud C" missiles, the conservative Sankei newspaper said, citing unidentified individuals familiar with Middle East affairs. The testing has been halted since July after one of the surface-to-surface missiles exploded at a military complex near the northern city of Aleppo, the Sankei said in its Washington-datelined story. The explosion took place at the site of a joint Iranian/Syrian project to fit short-range ballistic missiles with chemical warheads, according to Jane's Defense Weekly. Jane's cited Syrian defense sources as saying it happened during a test to fit a Scud C missile with a mustard-gas warhead when fuel caught fire at the production site. The North Koreans gave the Syrians advice on using chemical weapon warheads during discussions on safety procedures and related matters, the Sankei said. Western experts believe Syria has a stock of chemical weapons. However, Damascus has never acknowledged it has any weapons of mass destruction and has publicly called for ridding the Middle East of any such weapons. North Korea, which has provided Syria with missile technology and support since the 1980s, has rebuffed all overtures to sign an international treaty banning chemical weapons. Earlier this year, the IAF launched an air strike against a Syrian military installation that reportedly was a nuclear facility made with North Korean assistance. Damascus denies it has an undeclared nuclear program, and North Korea has said it was not involved in any Syrian nuclear project.