Syria's army pounded parts of the eastern belt of Damascus Tuesday (August 28th) as world leaders called for an investigation into mass killings in the town of Daraya.

The Syrian Observatory for Human Rights reported fierce shelling of the eastern neighbourhoods of Zamalka, Qaboon, Jubar and Ein Tarma while AFP reported the Syrian army launched an offensive targeting the rural Ghuta area east of Damascus.

The Observatory also reported heavy shelling by government forces Tuesday against opposition bastions in Aleppo and in the north-western town of Kafr Nabal in Idlib province, where at least 10 people were reported dead.

The latest round of violence comes one day after 190 people were killed across Syria, according to the Observatory. Concern is growing in the international community about the deaths of civilians during the conflict.

UN Secretary-General Ban Ki-moon on Monday demanded an independent inquiry into the killings of hundreds of civilians in the Syrian town of Daraya last week.

"The secretary general is certainly shocked by those reports, and he strongly condemns this appalling and brutal crime," Martin Nesirky, spokesperson for Ki-moon, told reporters.

"This needs to be investigated immediately in an independent and impartial fashion," the spokesperson added.

The Observatory said Tuesday that another seven unidentified bodies were found in Daraya, raising the number of corpses retrieved from the town to 340. Activists said the victims died as a result of a brutal five-day onslaught of shelling, summary executions and house-to-house raids by pro-government forces.

State media said the operation had "purified terrorist remnants" in Daraya, and the pro-government television station Al-Dounia said "terrorists" had carried out the killings.