Russian airstrikes in Syria: what you need to know about Vladimir Putin's bombing campaign

Russia launched airstrikes in Syria on Wednesday to aid its long time ally Bashar al-Assad in ridding the country of Isis, in a move that could plunge the four-year-old civil war into a volatile new phase.

Who

Vladimir Putin's decision, backed by MPs, to launch strikes in three Syrian provinces has been met with caution by the international community as it is thought it could further complicate the situation in Syria. US defence secretary Ash Carter said Russia was "pouring gasoline on the fire".

A US-led international coalition already carries out strikes in Isis-held areas around Aleppo, as well as Isis territory in Iraq, but the coalition has not targetted government forces or other rebel groups.

What

This is the part we're not clear on. Russia claims it is targeting solely Isis strongholds, rather than other enemies of the Syrian regime, or civilians. At least 30 civilian deaths have been reported so far, a claim that Russia has denied.

On Wednesday Saudi Arabia demanded that Russia end the bombing campaign "immediately", claiming Isis is not present in the areas targeted.

Where

US and French officials said the attacks had been in an area west of Homs, where Isis fighters are absent but where Assad's forces have been losing control to other rebel groups, some of which are backed by the West.

There are also reports from the secular Free Syrian Army that its assets had been hit by Russian jets.

Why

The four-year war in Syria, complicated by the ever-evolving presence of rebel groups, is not reaching a resolution any time soon.

The decision to launch strikes is Russia's biggest intervention in the Middle East in decades, and many think Putin is moving to forcefully stake out influence in the unstable region, or even to boost his own popularity back home.

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