Complex sentence: On 30 September 2015, Russia started military intervention in the Syrian Civil War, consisting of air strikes by Russia against militant groups opposed to the Syrian government, including al-Nusra Front, the Islamic State and the Army of Conquest.
Split into simpler sentences: On 30 September 2015, Russia started formal military intervention in the Syrian Civil War. It has consisted of air strikes by Russia against militant groups opposed to the Syrian government, including al-Nusra Front, the Islamic State and the Army of Conquest.