What have Russian airstrikes done in Syria?

It has been a year since Russia sent its Sukhoi supersonic jets and long-range bombers to rescue the faltering Syrian regime of Bashar al Assad.

The relentless aerial bombings have killed more than 3,500 civilians since the first missile struck opposition-held areas on September 30, 2015, accoding to Air Wars, a not-for-profit organisation keeping track of the Russian offensive.

The air cover hasn't helped Assad's forces to take back the cities where oppposition groups continue to defy his regime's rule.

"We have been overwhelmed with the data of human casualties coming in," Alex Hopkins of Air Wars told TRT World.

Air Wars and the London-based Syrian Observatory for Human Rights (SOHR) released seperate reports last week that contradict Russia's claim that civilians have not been targeted.

The devastation from the bombings is well documented and observers say the number of those killed is going to rise once latest figures are released.

"It will take us a while to sift through the data to ascertain the number of civilians killed in last couple of months," Hopkins says.

One problem for volunteers like Hopkins is the difficulty of distinguishing civilian deaths from those of combatants. The process could take weeks and months.

In the opposition-held areas of Aleppo city, homes have been reduced to rubble, children killed and even hospitals destroyed. Such is the fear of bombings that doctors at the four remaining hospitals there don't disclose their location for fear of retaliation.

Civilian Casualties

The Syrian conflict involves militaries from other countries besides Syria and Russia. The US also regularly carries out air raids against suspected DAESH targets.

But the Russian jets dropped bombs six times more than everyone else, according to Air Wars.

The airstrikes have resulted in deaths of anywhere between 3,000 and 7,000 civilians.

However, no one knows for sure exactly how many people have been killed in the bombings that included use of bunker busters, normally reserved for fortified military targets.

The Syrian Observatory for Human Rights says 3,804 civilians have been killed.

Air Wars puts the death toll at over 3,700.

But these stats don't cover the entire 12-month period. For instance, Air Wars reported figures for the duration up to January 31, 2016.

SOHR has also yet to release the figures for past five months.

The casualty figure is sure to go up if what has happened in recent months is taken into account. Just last month 391 civilians were killed in Russian bombings. More than 114 of them were children.

The barrel, incendiary and bunker buster bombs have caused such a destruction that few independent monitors dare go in cities like Aleppo.

As a result, the information that does trickle out is based on eyewitness accounts of rescue workers, social media updates and stories shared by oppposition group members.

Yet the Russian airstrikes have caused more misery than achieving any substantial goal. More than 4.8 million Syrians have been forced to flee their country and around 600,000 killed during the almost six-year conflict.

What has been achieved

Russian air power was crucial in helping Assad regime's ground forces to take back the ancient city of Palmyra in March this year.

The United Nations has designated sites in the city as world heritage, adding to the significance of its capture from the DAESH.

While Russian airpower has helped Assad's regime to regain control of some areas, vast swathes of land remain in control of oppposition groups.

The offensive had a fallout for Moscow's relations with Ankara as well. In November 2015, a Turkish F-16 shot down a Russian bomber that Turkey said crossed over into its territory.

It took months for the two erstwhile economic partners to mend their differences.

What remains to be seen is how far the Russian air support will go to help Assad's depleted and tired force.