By Albert Aji Barbara Surk
DAMASCUS, Syria - Four mortar shells exploded on Tuesday in central Damascus, killing 14 people and wounding scores, state media said.
The attacks in the Syrian capital come a day after President Bashar Assad announced his candidacy for the June 3 presidential elections, a race he is likely to win amid a raging civil war that initially started as an uprising against his rule.
The official SANA news agency said four shells struck in the capital's Shaghour neighborhood on Tuesday morning. State TV said 14 people were killed in the attacks and 86 were injured.
An official at the Damascus Police Command told The Associated Press that two of the mortar shells hit a school complex. The official spoke on condition of anonymity in line with government regulations.
No one immediately claimed responsibility for the attack. Rebels have frequently fired mortars into the capital from opposition-held suburbs.
SANA blamed the attacks on terrorists -- a term used by Assad's government for rebels fighting to oust him. Many of the opposition-held neighborhoods around Damascus have been under a crippling government blockade for months with no food and medicine allowed to reach trapped civilians inside.
Tuesday's attacks occurred just hours after an international rights organization accused Assad's forces of indiscriminately targeting civilians and civilian infrastructure with crude bombs in rebel-held districts of the northern city of Aleppo.
Human Rights Watch said its staff has documented 85 locations in Aleppo's opposition-held districts that government aircraft shelled with barrel bombs -- makeshift, shrapnel-packed explosive devices rolled out of helicopters.
The New York-based group identified the locations after interviewing witnesses and analyzing satellite imagery and video and photographic evidence, the report said.
The attacks in Aleppo occurred between Feb. 22 and April 2. The locations, identified by HRW, sustained damage that is "consistent with the detonation of barrel bombs," the report said. The organization also has evidence that government forces fired hundreds of mortar and heavy artillery shells during those 40 days.
Aleppo, Syria's largest city, has been carved up into rebel- and government-held neighborhoods since the opposition launched an offensive in the north in mid-2012.
HRW also criticized the opposition for firing mortars into populated, residential areas, but the rebel groups said government forces are behind most of the attacks that target residential areas and civilians.
The U.N. Security Council is meeting on Wednesday to review whether Syria's warring sides are complying with a resolution demanding the cessation of the use of barrel bomb and other weapons in populated areas.
Syria's conflict started as largely peaceful protests against Assad's rule in March 2011. It turned into a civil war after some opposition supporters took up arms to fight a brutal government crackdown on dissent. More than 150,000 have been killed, activists say, and millions have been displaced by the fighting.
Barbara Surk reported from Beirut.