At least six children have been killed in a Syrian government shelling of a girls' nursery in the rebel-held suburb of the capital of Damascus, monitoring groups have said.

Scores of others are also injured after the attack which struck the Banat Al Mostaqbal school, Arabic for Girls of the Future, in Harasta, shortly after 10am local time on Sunday (6 November).

A video uploaded onto Facebook and independently verified by Reuters documented the aftermath of the attack, showing blood splattered across the tiled floors alongside toys and the rubble.

A man in the video could be heard as saying that four children had died, 27 were injured and at least 53 people were inside the state-run school at the time of the shelling, before he was corrected to say five children had died.

The figure has since risen to six, which was confirmed by the activist-run Unified Medical Bureau of Eastern Ghouta.

It also reported that medical facilities in the suburb received tens of wounded children and adults following the attack, said the Independent.

The British-based Syrian Observatory for Human Rights has also reported the shelling and blamed the Assad government for the killings.

Images were also captured in makeshift hospitals near the bombing, where children could be seen receiving treatment. One boy could be seen wincing as his heart rate was checked.

The Syrian regime and its Russian allies say they target only militants, and that rebels are to blame for civilian casualties by operating in civilian areas. However, the West said the bombings deliberately targeted hospitals and aid workers.

More than 300,000 people have been killed in Syria since the conflict began in March 2011 with anti-government protests.

It comes as US-backed Arab and Kurdish military forces are reportedly preparing to launch an offensive to take Raqqa, the stronghold of Islamic State (Isis) in Syria.