Russia has reportedly carried out its first air strikes in Syria, a US official has told Reuters.
It comes just hours after Russian Parliament gave Vladimir Putin approval to use military force against so-called Islamic State in Syria.
According to the official, who was speaking on condition of anonymity, the military action was carried out in the vicinity of the city of Homs and American forces were given prior notice of the intended attack.
Footage posted on YouTube claimed to show Russian jets flying in the sky above Syria today:
Incursions by Russian jets into Turkish airspace have prompted a stern response from Nato's most powerful ally.
Here's what you need to know about this latest development in the increasingly bloody, complicated and volatile conflict.
Russia urges world leaders to unite to fight terrorism in Syria amid criticism that air strikes have targetted rebel fighters and civilians.