Russian air strikes in eastern Syria have killed more than 300 Islamic State militants and wounded 170 over the past two days, Russia's Defense Ministry said on October 3.
Those killed included Abu Islam al-Qazaqi, a field commander from the Central Asian country of Kazakhstan, and about 40 militants who came from southern Russia, ministry spokesman Igor Konashenkov said in an emailed statement.
Moscow has repeatedly voiced concerns about citizens of former Soviet republics such as Kazakhstan fighting for Islamist extremist groups in Syria and Iraq.
This week's air strikes were conducted on the eastern bank of the Euphrates River, the statement said.
Russian President Vladimir Putin said earlier this year that as many as 10,000 fighters from the former Soviet Union may have joined Islamic State.
Syria is embroiled in a six-year civil war that has killed more than 330,000 people and forced an estimated 5 million more to flee across borders to become refugees.
Russia and Iran support the government of Syrian President Bashar al-Assad, while the United States and Turkey back rebel groups.
Also on October 3, Islamic State claimed responsibility for a pair of suicide bombings in the Syrian capital, Damascus, that killed 17 civilians and security forces the previous day.