Britain-based Syrian Observatory for Human Rights said on Wednesday that Russian airstrikes in Syria have killed 1,015 civilians, including more than 200 children. The monitor said the airstrikes, which began around four months ago, have also killed 893 Islamic State jihadis and 1,141 other militants. Of the 3,049 total deaths, nearly 700 were reported in the last three weeks, it said.

The observatory added that airstrikes carried out by the United States-led coalition have killed 4,256 people since they began in September 2014. This includes 90 children among 322 civilians. These airstrikes have also killed 3,787 IS fighters and nearly 150 militants from other extremist groups, reported AFP.

Russia, a staunch ally of the Syrian government, had earlier denounced accusations that its raids have killed civilians as "absurd", and said claims by rights groups were made up of "cliches and fakes".