Turkish Foreign Minister Feridun Sinirlioglu on Thursday expressed "serious concern" over reports that Russia's first air strikes in Syria hit civilians and anti-regime rebels rather than Islamic State (IS) jihadists.

"We feel serious concern over the information that Russia's air strikes in Syria targeted opposition positions instead of Daesh (IS) and that as a result civilians also lost their lives," Sinirlioglu said, quoted by the state-run Anatolia news agency.