Mortar shells hit Damascus

The official SANA news agency reported Tuesday that several shells slammed into central Damascus, hitting a school complex and killing at least 14 people.

"Fourteen citizens were killed and 86 others wounded by terrorists who targeted the Shaghur neighborhood in Damascus with four mortar shells," the SANA news agency said, using the word terrorists to refer to rebels fighting to oust President Bashar al-Assad.

The Britain-based Syrian Observatory for Human Rights also reported the mortar attack but said the death toll was higher, at 17 people killed.

No one has immediately claimed responsibility for the attack.

The mainly Sunni Muslim rebel fighters frequently launch mortar shells and rockets into government-held areas, from their positions on the outskirts of the capital. The Shaghour neighborhood is a mainly Shiite Muslim district.

Assad re-election bid

The attack came a day after President Bashar al-Assad nominated himself to stand for re-election on June 3. His bid comes amid growing calls for him to step aside and allow a political solution to de-escalate Syria's civil war.

Although al-Assad is among one of seven candidates, he is widely expected to win. However, the polls will only take place in parts of Syria controlled by government forces, which will exclude many voters. New election rules also require candidates to have lived in the country for the last decade, which bars key opposition figures in exile from standing for office.

The conflict in Syria started in March 2011 after a government crackdown on largely peaceful protests against Assad's rule. More than 150,000 are believed to have been killed and millions of others displaced by the fighting.

hc/pfd (Reuters, AFP, AP)