Radical jihadist group ISIS has seized 88 pounds of uranium from a research facility at Mosul University, Reuters reports.

“Terrorist groups have seized control of nuclear material at the sites that came out of the control of the state,” says a Tuesday letter from the Iraqi ambassador to the U.N., who explained that it “can be used in manufacturing weapons of mass destruction.”

“These nuclear materials, despite the limited amounts mentioned, can enable terrorist groups, with the availability of the required expertise, to use it separate or in combination with other materials in its terrorist acts.”

A U.S. government source told Reuters that the uranium is likely unenriched, meaning it cannot be used for nuclear weapons. Unenriched uranium can, however, be used to fuel nuclear reactors, though at much larger quantities. A different official, downplaying the significance of the acquisition, said that he was unaware of it worrying U.S. authorities. (RELATED: US Partially Evacuates Baghdad Embassy As ISIS Marches On)

U.S. officials have also downplayed ISIS’s June seizure of a Hussein-era chemical weapons depot near Baghdad, with Department of Defense spokesman Adam Kirby saying “Whatever material was kept there is pretty old and not likely to be able to be accessed or used against anyone right now.” The seizure came to light after an earlier letter from the Iraqi ambassador notified the U.N. that Iraq is unable to “fulfill its obligations to destroy chemical weapons” because of worsening security conditions.

The Iraqi ambassador’s letter is the latest plea from the Iraqi government for international assistance combating ISIS, who declared a caliphate earlier this month and now control large swathes of Iraq and Syria. (RELATED: ISIS To Destroy Ancient Biblical Artifacts In Northern Iraq)

The Iraqi ambassador to the U.S. has repeatedly asked for airstrikes, which the Obama administration has thus far refused to authorize. Meanwhile Prime Minister Nouri Al-Maliki has accepted military assistance from Russia, Syria, and Iran. (RELATED: Snubbed By The US, Iraq Looks To Putin For Help)

The Iraqi government continues to crumble from within, with support for the prime minister weakening by the day. Iraq’s first parliamentary session after their April elections ended with minority parties storming out in opposition to Maliki earlier this month, and on Wednesday Kurdish representatives decided to boycott cabinet meetings entirely after Maliki publicly accused them of harboring ISIS insurgents.

Iraq acceded to the Convention on the Physical Protection of Nuclear Material on Monday, “the only international legally binding undertaking in the area of physical protection of nuclear material.”

According to the International Atomic Energy Agency, “it establishes measures related to the prevention, detection and punishment of offenses relating to nuclear material.”

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