Russia's air campaign in Syria has killed hundreds of civilians and caused massive destruction in residential areas, CNN said citing a report released Wednesday, December 23 by Amnesty International.

The rights group claims the pattern of attacks "show evidence of violations of international law."

Russia has been engaged in a military campaign in Syria in support of embattled President Bashar al-Assad since September. Moscow says its operation is aimed at defeating "terrorist targets" there, but the United States claims the Russian airstrikes are targeting Syrian opposition forces rather than ISIS, which has taken control of large parts of the country.

The Amnesty report, entitled "Syria: Civilian Objects Were Not Damaged: Russia's Statements in Syria Unmasked," singles out six attacks it says took place in the Syrian cities of Homs, Idlib and Aleppo between September and November this year, which claimed the lives of at least 200 civilians and around a dozen Syrian rebel fighters. The group also claimed Russia covered up damage to a mosque in one air strike, and a field hospital in another.