MOSCOW (AP) — The Russian military says that tens of thousands of its troops have fought in the war in Syria.

Russia has waged a military campaign in Syria since September 2015, helping President Bashar Assad's forces reclaim significant territory they had lost to rebels and militant groups.

The ministry said Wednesday that over 63,000 Russian troops, including 434 generals, have fought in Syria and about 90 percent of Russian combat pilots have flown in Syria.

The Russian military has used the operation to test some of its most advanced weapons, including the latest jets and cruise missiles.

It has helped turn the tide of war in Assad's favor — the Syrian government now controls nearly two thirds of the country, compared to just one third back in 2014.