A key Russian official said on Wednesday the U.S. has trained former ISIS fighters in Syria in an effort to further destabilize the war-torn country.

General Valery Gerasimov told Komsomolskaya Pravda newspaper that the U.S. has trained former militants for the Islamic State in Iraq and Syria (ISIS) terror organization at its military base in Tanf, which is strategically located in southern Syria near its border crossing with Iraq, according to Reuters.

“They are in reality being trained there,” the general told the news wire.

ADVERTISEMENT

“They are practically Islamic State,” he continued. “But after they are worked with, they change their spots and take on another name. Their task is to destabilize the situation.”

Gerasimov said the former fighters now refer to themselves as the New Syrian Army or other names.

The U.S. has said that the base in Tanf is a temporary facility used for training partners to fight ISIS. It has denied similar Russian allegations in the past.

Gerasimov's comments come as U.S.-Russian tensions have ratcheted up in Syria.

The two countries have expressed a shared interest in driving ISIS fighters out of Syria; however, they find themselves on opposite sides of Syria's civil war, with Moscow throwing its support behind Syrian President Bashar Assad and the U.S. supporting rebel fighters.