The commander of a group of Syrian fighters trained by the United States has been kidnapped by Al-Qaida's affiliate in Syria, his group said Thursday.

The commander, Nadeem Hassan, and seven of his fighters were taken by the Nusra Front, a rival of the Islamic State in Iraq and the Levant, as they were returning from a meeting in Turkey.

A contingent of 54 fighters from Hassan's group, known as Division 30, are the only ones who have graduated from a Pentagon program to train Syrian rebels to fight ISIL in Syria. One of the fighters taken with Hassan was his deputy, Farhan Al-Jasem, who commands the fighters who graduated from the U.S. training program.

A Pentagon spokeswoman, Cmdr. Elissa Smith, would not say if any trainees of its program had been taken in Syria. Working with the Americans can make insurgent fighters a target for hard-line jihadists.