Two booby-trapped cars blew up at Syrian security sites in Damascus on Friday, state television said, and witnesses heard large blasts rock the capital. Later, Al Manar TV reported that 30 people were killed in the attacks.
"The terrorist attacks left a number of martyrs, both civilian and military. Most of the victims were civilian," Syrian TV said in a news flash.
State television also claimed that initial investigations indicated that al Qaida was behind the attacks. A witness from the Syrian Observatory for Human Rights said he heard heavy gunfire break out after the blasts.
A witness who spoke to Reuters by telephone said he heard two blasts rock the capital, and a second witness from the Syrian Observatory for Human Rights reported sounds of heavy gunfire after the explosions..
Friday's attacks hit a state security administration building and a local security branch, state television said.
The Arab League monitors who began arriving on Thursday will have the job of checking if Syria is complying with an Arab initiative that calls for an end to violence, the withdrawal of troops from the street and the release of prisoners.
Earlier Thursday, a human rights group said that more than 6,200 people including hundreds of children have died in Syria's crackdown on an anti-government revolt.
Syria is facing increasingly fierce international condemnation for its handling of months of demonstrations against President Bashar Assad’s rule, partly inspired by the “Arab Spring" uprisings that have swept across North Africa and the Middle East.
Syria says it is fighting foreign-backed "terrorists" and on Thursday announced that more than 2,000 of its security forces have been killed in the unrest.
The British-based Avaaz rights group said it had collected evidence of more than 6,237 deaths of civilians and security forces, 617 of them under torture. At least 400 of the dead were children, it added.
The figures were about 1,000 higher that the latest UN estimates, which have also been climbing sharply in recent months.
“No once can now turn a blind eye to the horror-show in Syria ... One in every 300 Syrians has either been killed or imprisoned," said Avaaz executive director Ricken Patel in a statement.
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