In a 2008 paper published by the Korea Economic Institute, Dr. Christina Lin of Jane’s Information Group noted that “Increased visits to Iran by DPRK [North Korea] nuclear specialists in 2003 reportedly led to a DPRK-Iran agreement for the DPRK to either initiate or accelerate work with Iranians to develop nuclear warheads that could be fitted on the DPRK No-dong missiles that the DPRK and Iran were jointly developing. Thus, despite the 2007 National Intelligence Estimate stating that Iran in 2003 had halted weaponization of its nuclear program, this was the time that Iran outsourced to the DPRK for proxy development of nuclear warheads.”

Another noteworthy detail: According to a 2003 report in the L.A. Times, “So many North Koreans are working on nuclear and missile projects in Iran that a resort on the Caspian coast is set aside for their exclusive use.”