"Very disturbing video footage has emerged purporting to show the aftermath of a mortar bombardment on the Yarmouk Palestinian refugee camp in south-east Damascus.
As mentioned earlier doctors said at least 20 people were killed in the attack. Witnesses told Reuters that mortars hit a busy street.
Activists named the road as al-Ja'ouneh street.
The Syrian Observatory for Human Rights says the death toll has risen to 21, including two children.
The following video, uploaded by the Observatory, shows a smoke-filled street strewn with rubble and dead bodies. Warning: it contains distressing images."