The Department of Defense has a procurement contract for helicopters from Rosoboronexport, the Russian Federation’s official arms export firm providing weapons to Assad in Syria. Rebels are fighting the Assad regime, and he has been accused of killing thousands of his own people. President Obama recently pledged to send U.S. arms to the Syrian rebels to aid their effort. Lawmakers have argued that the U.S. government shouldn’t be funding a group that aids someone the country is also opposing in the Syrian civil war.

“While Rosoboronexport receives huge payments from DoD, it also continues to serve as a key enabler of atrocities in Syria, transferring weapons and ammunition to prop up the bloodthirsty regime of Bashar al-Assad,” the letter stated. “As such, DoD has put American taxpayers in the repugnant position of subsidizing the mass murder of Syrian civilians.”

The senators also pointed out that Russia has a propensity for “corruption” and warned that U.S. taxpayer dollars could be at risk.

“While DoD’s relationship with this firm is troubling on many levels, the prospect that American taxpayers have been made into unwitting victims of Russian corruption demands special scrutiny,” the senators wrote. “We are concerned by DoD’s apparent failure to consider the strategic implications of sourcing mission-critical military equipment from a potentially hostile power such as Russia.

“We need your personal assurance that American taxpayers are not being cheated out of their hard-earned dollars by corrupt Russian officials and contractors who may be lining their own pockets.”

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