The United States military has begun training Syrian rebels to combat the Islamic State of Iraq and Syria (ISIS). The training of Syrian rebels further drives the U.S. deeper into the violent conflict in the Middle East, eight months after sending strategic airstrikes against the Sunni extremists.

Defense Secretary Ash Carter stated that the U.S. military has already started training 90 Syrian fighters, who are to be the first batch of rebels that the U.S. will train. Apart from the training, the Syrian fighters will also be receiving a stipend and some still-undefined support once they engage ISIS in combat, according to Reuters.

The first batch of fighters are currently being trained in Jordan, which is the first training site that is being handled by American forces, according to CBS News. Training in Saudi Arabia, Qatar, and Turkey, are also set to start this coming weekend.

Approximately 3,750 Syrian rebels have signed up to be trained by the U.S. military, with about 400 more to come after having passed the prescreening. Each class of trainees can have as much as 300 in number, according to CBS News.

A spokesman from the Jordanian government, Mohammed Momani, stated in an interview with the Associated Press that the program to train the rebels have already started "a few days ago."

"Jordan confirms that the war against terrorism is our war, and it's the war of the Muslims and Arabs, first and foremost, to protect our interests and the security of our countries, peoples and the future of our children, and to defend our tolerant religion," he stated.

The program however, is not without its share of detractors. A number of lawmakers have already stated that the program is too small and too slow. A forecast by the Pentagon states that it may take up to three years in order to fully train and arm 15,000 rebels, according to Reuters.

Carter states that though the progress of the program may be slow and minute, it is nonetheless strategic.

"We're starting with the people that we have that we've vetted very carefully," he stated during a news briefing.

"We expect that to be successful and therefore to grow. But you have to start somewhere, and this is where we're starting," he added.