Russia’s top general accused the U.S. military of training former Islamic State (ISIS) soldiers at an army base in Syria in order to cause havoc in the country.

General Valery Gerasimov, who is chief of the Russian General Staff which oversees all Russian armed forces, leveled the allegations against the U.S. in Russian newspaper Komsomolskaya Pravda Wednesday.

Gerasimov said that a military base in the Al-Tanf region of Syria is being used to re-train the former ISIS combatants, give them a different name like New Syrian Army and send them out to destabilize the country. The civil war in Syria has raged since 2011 between the government led by President Bashar al-Assad and a number of insurgent forces.  Russia has backed al-Assad but has partially withdrawn its troops out of the country. The unrest in Syria allowed ISIS, the self-styled jihadist extremist group, to control parts of the country, but the group has now lost almost all of its territory.

Gerasimov claimed that the U.S. gathered 400 former ISIS soldiers at the base in al-Tanf citing satellite intelligence.

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

The U.S. has routinely denied training ISIS or avoiding fighting the militant group. The U.S. said the military base is a temporary facility to train partner forces to fight ISIS, according to Reuters. The U.S. had focused its forces in Syria on destroying ISIS since the group came to prominence in 2014. The U.S. led coalition fighting the group said that there were fewer than 1,000 ISIS militants left in Syria and Iraq Wednesday.

“Due to the commitment of the Coalition and the demonstrated competence of our partners in Iraq and Syria, there are estimated to be less than 1,000 ISIS terrorists in our combined joint area of operations, most of whom are being hunted down in the desert regions in eastern Syria and Western Iraq,” the coalition said in a statement to Reuters.

Separately on Wednesday  Russian Foreign Minister Sergei Lavrov said that the main mission of destroying ISIS in Syria was finished and that the next task would be taking out Islamist Extremist group Al-Nusra Front.

Iraq declared victory against ISIS earlier this month.