General Austin: Only '4 or 5' US-Trained Syrian Rebels Fighting ISIS

Only 100 to 120 others are currently in training.

Christine Wormuth, the Under Secretary of Defense for Policy, also told the Senate Armed Services Committee that there are currently between 100 and 120 fighters in a program that was slated to have trained 5,400 fighters in its first 12 months.

Austin told the panel that goal was not going to be met and that options are being explored about how to retool the program which was intended to train moderate Syrian rebels to fight ISIS. So far, $42 million has been spent to develop the $500 million program which began training in April.

Wormuth said the number of trainees in the program was “definitely smaller than expected” and attributed the low number of trainees to the stringent vetting standards being used by Centcom to prevent extremists from entering the program.

"I have never seen a hearing that is as divorced from the reality of every outside expert and what you are saying," McCain told Austin.

A U.S. official has told ABC News that the initial group of 54 fighters was not effective from the time they re-entered Syria

Already integrated into the large umbrella rebel group known as Division 30, the U.S. official said that the fighters were allowed to visit family members for the holiday. That included some who were in Syria or in refugee camps in Turkey.

That dispersion resulted in some of the fighters who went to visit Turkey being trapped there when Turkey closed its borders. Another group of fighters who visited family had not yet returned to their unit when the attack occurred.

A third group of fighters broke off from the main group to follow a leader who had chosen to fight Assad regime forces instead of ISIS.

Only a handful of the fighters had returned from the Eid holiday to rejoin Division 30 when they were attacked by the Al Nusra fighters. It was this group of fighters who called in five U.S. airstrikes to repel the attack.

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