BEIRUT (AP) — Two car bombs exploded in southern Syria and a rocket slammed into a building in the north in a spike in civil war violence today that Syrian state media blamed on rebel fighters trying to topple President Bashar Assad.

The rocket attack in the northern city of Aleppo and the suicide car bombings in Daraa, south of Damascus, occurred during a particularly bloody week nearly two years after an uprising began against Assad’s regime. On Thursday, opposition activists said pro-government militia swept through a town in central Syria, torching houses and killing more than 100 people.

Both sides have been blaming each other for the recent attacks, and it was the second time in a week that the government accused rebels of firing rockets.

The state-run SANA news agency said the morning attack in Aleppo was carried out by terrorists, a term the regime uses for rebels. But the Local Coordination Committees of Syria, an activist group, and the Aleppo Media Center, a network of antiregime activists, accused the government of launching an airstrike.

On Tuesday, 87 people were killed in twin blasts at Aleppo University. The regime said rebels hit the university with rockets. Rebels said the deaths resulted from regime airstrikes.

Syria’s state-run TV claimed that shortly after the rocket hit the building in Aleppo, militants linked to an al-Qaida group detonated cars filled with explosives near a mosque in Daraa as worshippers were leaving following Friday prayers.

Video broadcast on Syrian state TV showed several floors of the targeted building collapsed in a governmentcontrolled area of Aleppo, Syria’s largest urban center and main commercial hub.