BEIRUT -- Two explosions struck security compounds in the Syrian city of Aleppo on Friday, killing 25 people and wounding 175, state media reported, in a major city that has largely stood by President Bashar Assad in the nearly 11-month-old uprising against his rule.
The blasts come as escalating violence between regime forces and an increasingly militarized opposition has raised fears the conflict is spiraling toward civil war.
A Syrian offensive aimed at crushing rebels in the battered city of Homs continued Friday, with soldiers who have been bombarding the city for the past six days making their first ground move to seize one of the most restive neighborhoods.
State TV blamed "terrorists" for the blasts in Aleppo -- the first significant violence in Syria's largest city -- saying they were proof the government is facing a violent enemy. Anti-Assad activists accused the regime of setting off Friday's blasts to discredit the opposition and avert protests that had been planned in the northern city on Friday.
Along with the capital Damascus, Aleppo is Syria's economic center, home to the business community and prosperous merchant classes whose continued backing for Assad has been crucial in bolstering his regime. The city has seen only occasional protests.
Three earlier bombings in Damascus in December and January that killed dozens prompted similar exchanges of accusations. Nobody has claimed responsibility for any of the attacks.
Outside one of the compounds hit, the Military Intelligence Directorate, a weeping correspondent on state-run TV showed graphic footage of at least five corpses, collected in sacks and under blankets by the side of the road.
Debris filled the street and residential buildings appeared to have their windows shattered. But the location did not appear to be closed off, as local residents milled around the site, with few uniformed police around. No emergency vehicles or ambulances were visible in the footage and there was no sign of wounded, as earth-moving equipment was seen clearing the rubble.
The presenter said the blast went off near a park and claimed children were among the dead, although none were seen in the TV footage.
The second blast went off outside the headquarters of a police force in another part of the city. State television cited the Health Ministry as saying 25 people were killed in the two blasts and 175 were wounded.
Mohammed Abu-Nasr, an Aleppo-based activist, blamed Assad's regime for the explosions, insisting the opposition would not carry out bombings in residential areas.
"The opposition and the Free Syrian Army don't kill civilians," Abu-Nasr said, referring to the force of army defectors that frequently attacks regime military forces.
Abu-Nasr said the blasts came on a day when activists were planning wide protests in the city after the Friday prayers. "Despite the blasts, we will go out and protest today," he said.
So far, Assad's opponents have had little success in galvanizing support in Aleppo, in part because the business leaders have long traded political freedoms for economic privileges. The city of around 2 million also has a large population of Kurds, who have mostly stayed on the sidelines of the uprising since Assad's regime began giving them citizenship, which they had long been denied.
The Aleppo blast was the latest in a string of bombings that the regime has sought to blame on the opposition, which denies any role. On Jan. 6, a suicide attack in the capital Damascus killed 26 people. Two weeks earlier, 44 people were killed in twin suicide bombings that targeted intelligence agency compounds in Damascus.
Assad's crackdown has killed more than 5,400 people since the uprising began in March.
The assault on Homs began last Saturday after unconfirmed reports that army defectors and other armed opponents of Assad were setting up their own checkpoints and taking control of some areas.
Hundreds of people are believed to have been killed in the past week in Homs from relentless shelling and gunfire on several rebellious neighborhoods in the city, an operation activists said aimed to soften up the areas before moving in.
On Friday, soldiers backed by tanks pushed into the neighborhood of Inshaat. The Britain-based Syrian Observatory for Human Rights said troops were going house to house detaining people. Inshaat is next to Baba Amr, a neighborhood that has been under rebel control for months. Activists said at least four people were killed in the shelling in Baba Amr on Friday.
"They are punishing the residents," said the Observatory's chief Rami Abdul-Rahman, who added that food supplies were dwindling in the area.
Troops shelled parts of the city with tanks and heavy machine guns through the night until daylight Friday, said Majd Amer, an activist in Khaldiyeh, one of the targeted districts. He said troops nearby appeared to be preparing to move into Khaldiyeh as well.
Mohammed Saleh, a Syria-based activist, said the regime appears to be trying to take over rebel-held areas in Homs and the northwestern restive province of Idlib before Feb. 17, when Assad's ruling Baath party is scheduled to hold its first general conference since 2005.
The conference is expected to move on reforms that Assad has promised in a bid to calm the uprising. During the conference, Baath party leaders are expected to call for national dialogue and announce they will open the way for other political parties to play a bigger role in Syria's politics.
The opposition has rejected such promises as insincere and said it will not accept anything less than Assad's departure.
State media also reported this week that a committee in charge of drafting a new constitution reportedly removed a section naming the Baath party as the leader of the nation and society, once a key demand by the opposition.
The Observatory and the Local Coordination Committees, another activist group, also said troops opened fire to disperse thousands of protesters who filled the streets following Friday prayers in the northwestern coastal city of Latakia, the southern city of Daraa, Homs and the Damascus suburbs.
The groups did not have immediate word on casualties during protests, but said four army defectors died in a clash with troops in the Damascus suburb of Dumair.
Bassem Mroue can be reached on twitter at http://twitter.com/bmroue