“U.S. taxpayers should not be put in a position where they are indirectly subsidizing the mass murder of Syrian civilians,” wrote the senators, led by Sens. John Cornyn (R-Texas), Dick Durbin (D-Ill.), Kelly Ayotte (R-N.H.) and Kirsten Gillibrand (D-N.Y.).
The company has a $375 million contract with the Defense Department signed in 2011 to provide 21 dual-use Mi-17 helicopters for the Afghan military.
Cornyn questioned Panetta and Joint Chiefs Chairman Gen. Martin Dempsey about the contracts at a Senate Armed Services hearing on Syria last week. At the time, the Pentagon officials said they were not aware of the specifics of the relationship with the company.