In the Idlib province town of Khan Sheikhoun, activists said the Syrian army was battling the rebels after protesters and a U.N. convoy came under fire in the wake of a funeral.
In one video spread by activists, a man holding a grenade says rebels destroyed a government tank after the attack, pointing to what appears to be a tank set ablaze, streaming dark smoke.
An activist known as Aous said the two sides also sparred in his town, Deir-al-Zor, after U.N. observers met Monday with the families of Syrians who had been killed and detained.
"Today, security forces took revenge," shelling part of the town, Aous said in an interview over Skype. "In the beginning, the Free Syrian Army was not sure whether to answer or not because of the cease-fire. But when the situation got worse, the clashes started."
Seven people were reportedly killed there, said Aous and other activists. Across the country, at least 48 people had been killed Tuesday, the Local Coordination Committees activist network said.
Syrian state media reported that terrorists had set off an explosion while preparing a bomb in the city of Baniyas, killing themselves and a child. It was unclear exactly how many people had been injured or killed. State media usually refer to the armed rebels as terrorists.
Dissidents said government shelling also continued in the town of Rastan and around Qusayr. An activist known as Rami Kamel said seven people had been killed so far in towns near Qusayr that harbored defected soldiers and families who had fled from the violence in Homs.
More than 10,000 people are believed to have died since the Syrian uprising against President Bashar Assad broke out more than a year ago, including regime forces, opposition fighters and civilians.
-- Rima Marrouch in Amman and Emily Alpert in Los Angeles
Photo: A girl walks past Syrian rebels in the Khaldiyeh neighborhood in Homs province on Monday. Credit: Fadi Zaidan / Associated Press