A Washington-based think tank said Wednesday it was impossible to confirm a 2015 article by the German weekly Der Spiegel claiming that Syria was developing another nuclear reactor to replace the one Israel destroyed in 2007. However, it urged the international atomic watchdog to investigate the site in which Syria – possibly aided by Iran and North Korea – was allegedly trying to set up a new nuclear base to cover for the one Israel destroyed.

The results of the investigation by the Institute for Science and International Security were published hours after Israel took responsibility for the 2007 attack at Deir el-Zour in northeast Syria.

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According to Der Spiegel, a new underground facility was launched in the center of a mountain into which a tunnel network had been dug. Located in a remote, rugged region near Qusayr in western Syria, the facility was said to be connected to a power plant and a water source for cooling.

Open gallery view Top security think tank ISIS says can’t confirm that Syria is building another nuclear plant Credit: Institute for Science and International Security

Experts who viewed satellite photos told the magazine the facility was meant for uranium enrichment. The Syrians had transferred 8,000 fuel rods to the facility, Der Spiegel added.

But the Institute for Science and International Security said it could not confirm the report by the German magazine. (Click here for full report)

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Syrian nuclear reactor attack: Step by step

“Based on commercial satellite imagery, none of these claims could be confirmed, and the purpose of the site remains unknown,” the think tank wrote.

“However, some imagery observations are consistent with Der Spiegel’s reporting. Although we fully understand the limitations and risks of the following approach, we believe that this site warrants inspection by the International Atomic Energy Agency, even though accomplishing such inspections may have to wait until the Syrian conflict ends."

As the think tank put it, “a nuclear reactor located fully underground is not impossible, but it poses a huge engineering challenge and would likely require secret, on-going assistance from North Korea.

“Similarly, an enrichment plant would require extensive foreign assistance, likely from North Korea or possibly from Iran, since there is no available evidence of Syria buying the necessary equipment and materials from abroad. In any case, learning the purpose of this site should be a priority. A visit by the IAEA makes sense, even though accomplishing that may have to wait until the Syrian conflict ends.”

Open gallery view Top security think tank ISIS says can’t confirm that Syria is building another nuclear plant Credit: Institute for Science and International Security

It added: “Any nuclear-related facility in Syria could involve considerable assistance from North Korea, given that Pyongyang provided extensive assistance in the construction of the Al Kibar reactor, which Israel destroyed in 2007.”

The think tank also warned about the possibility that Syria was storing materials from the destroyed site. “An enduring mystery ... is the fate of key remnants of the reactor project, such as stockpiles of natural uranium, fuel fabrication capabilities, and even possibly plutonium separation capabilities that may have remained in Syria and continue to pose a proliferation risk,” it wrote.

The authors added that “Israel’s action serves to highlight once again the lack of accounting for Syria’s past nuclear weapons program and the location of any assets remaining from that program.”

They concluded: “Understanding North Korea’s role in Syria is also important as the United States weighs the prospects of negotiations with North Korea."