Seven civilians were killed and dozens wounded when terrorist gunmen fired a barrage of rockets and mortar rounds Sunday at central Damascus.

Seven civilians were killed and dozens wounded when terrorist gunmen fired a barrage of rockets and mortar rounds Sunday at central Damascus.

The terrorist attack came two days after they threatened to retaliate for the Syrian army operation against a gunmen-held area on the edge of the capital.

"Seven civilians have been killed and dozens more wounded, as rebels in the Eastern Ghouta area fired more than 43 locally made rockets and mortar rounds at several areas of central Damascus," the opposition Britain-based Syrian Observatory for Human Rights said.

Among the areas hit were the Al-Maliki and Mazzeh neighborhoods, as well as Arnus and Sabaa Bahrat squares, said the opposition group.

State news agency SANA said the army fired back at the source of the incoming fire in Eastern Ghouta.

The attack came two days after Zahran Alloush, the head of the terrorist Jaysh al-Islam (Army of Islam) group, warned on Twitter that his forces would launch a "rocket campaign against the capital" from Sunday.

He wrote that rockets would "rain down every day... in retaliation for the army air raids" against gunmen strongholds in Eastern Ghota.

Government aircraft on Friday carried out a series of raids against gunmen-held Hammuriyeh in the besieged Eastern Ghota area east of Damascus.

Syria was hit by a violent unrest since mid-March 2011, where the western media reports accuse countries, mainly the USA, Turkey and Saudi Arabia of orchestrating the civil conflict in the country and providing terrorist groups with money, weapons and trained mercenaries.

On May 2011, Syrian army launched a wide-scale operation against armed groups and gunmen operating in the country, who started to escape the army blows and infiltrate illegally to Lebanon.