Regime troops used tear gas on Saturday to try to disperse a mass funeral attended by thousands of people who took to the streets of the Syrian capital to mourn slain protesters, a rights group said.
"Syrian regime forces used tear gas to disperse people attending the funerals of the Kfar Sousa martyrs and calling for the fall of the regime," the Britain-based Syrian Observatory for Human Rights said.
The protests were staged after blasts rocked Damascus and the country's second city Aleppo earlier on Saturday, killing several people, the Observatory said.
The latest violence came just two days before a scheduled parliamentary election in Syria, where the regime of President Bashar al-Assad has been trying to crush an uprising since March last year.
One explosion hit a car wash as a bus was passing in a suburb of Aleppo, the country's commercial hub in the north, said Rami Abdel Rahman of the Syrian Observatory.
At least five people were killed in the blast, he told AFP in Beirut.
Aleppo has been the scene of escalating violence in recent days, including a regime raid on the university, according to the Observatory.
Two blasts also hit Damascus on Saturday, Abdel Rahman said. "One explosion occurred inside the city, and the other hit the periphery" where three soldiers were wounded, he added.
Television footage showed a mangled car destroyed by one of the explosions that tore through a city street.
Abdel Rahman accused the regime of launching the attacks to stop funerals a day after the security forces killed 30 anti-regime protesters, including nine in the Kfar Sousa and Tadamon districts of Damascus.
The Observatory says more than 600 people have been killed nationwide during a tenuous truce that went into effect April 12.
Also in Damascus, troops opened fire in the central neighborhood of Barzeh, as they carried out multiple raids and made arbitrary arrests, the watchdog said.
Despite the violence, mourners took to the streets of Kfar Sousa, just under a kilometer from the prime minister's office, as shown in an amateur broadcast posted online by activists.
Opposition bloc the Syrian National Council had called on the small force of United Nations observers already in the country to visit Kfar Sousa and Tadamon.
"The funerals will show the regime that Damascus is not a neutral city as they pretend," it said in a statement.
Internet footage showed one mass funeral-turned-protest in Kfar Sousa after Friday's killings there.
"Syria wants freedom!" and "God is great!" chanted protesters. "We salute the [rebel] Free Syrian Army," read one slogan painted on a wall in Kfar Sousa.
Holding up pictures of some of the nine people the security forces killed in Damascus on Friday, mourners also denounced sectarianism, chanting that "the Syrian people are one."
Hundreds of people also took to the streets to honor the dead in the Tadamon area, video footage posted online by activists showed.
It was not immediately possible to verify the authenticity of such footage posted online.
Elsewhere in Syria, the Observatory reported that unidentified gunmen assassinated an official of the ruling Baath party in the northwestern province of Edleb.
Part of a six-point blueprint for peace, the shaky ceasefire deal was brokered by UN and Arab League envoy Kofi Annan, whose office said on Friday that his plan was still "on track."
Under the plan, the Assad government agreed to withdraw its troops and heavy weapons from urban areas and allow peaceful demonstrations.
"The Annan plan is on track and a crisis that has been going on for over a year is not going to be resolved in a day or a week," Annan's spokesperson in Geneva, Ahmad Fawzi, told journalists.
On Friday, protesters had emerged from mosques after weekly prayers across the country, calling for Assad's ouster, said the Observatory.
At least 30 civilians were reported killed during the day, among them a couple and their child shot dead in Aleppo, scene of a bloody regime raid the day before in which four university students died.
Another 200 students were arrested in what the Observatory said could prove a turning point of the uprising in the city, largely spared by the violence so far.
Overall, the Observatory estimates that more than 11,000 people have been killed in the 14 months since the outbreak of the revolt.
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