An opposition group, Local Coordination Committees of Syria, said at least 11 people were killed across the country, CNN reported.
In Aleppo CNN said residents had to wait nearly two hours to receive free bread being provided by the rebel army.
"More than 600 probable artillery impact craters" can be seen in satellite photos of Anadan, a town near Aleppo, Amnesty International said.
In Aleppo, fighting escalated as a rebel stronghold was hit by regime aircraft in an attack that killed nine members of a family in a nearby house and forced the rebel fighters to move to a new base in the city, witnesses and activists said.
On Monday, rebels struck again close to the leadership's core, bombing the third floor of the state TV and radio headquarters, which has been used to reassure Syrians President Bashar Assad remains in control.
No one was seriously injured in the bombing and broadcasts continued uninterrupted, state TV said.
Also in Damascus, a spokesman for the Free Syrian Army said three of the 48 Iranians that rebels have been holding since Saturday were killed Monday in shelling by regime forces. The FSA threatened to execute the remaining 45 unless the firing stopped.
Shiite-dominated Iran, Assad's closest ally, insists the Iranian hostages are religious pilgrims and has asked Sunni-led Qatar and Turkey to intervene. However, the FSA says they are members of Iran's Republican Guard.
The Washington Post reported that Saeed Jalili, head of Iran's Supreme National Security Council and its chief negotiator on nuclear operations visited Damascus Tuesday and met with Assad. He apparently was to discus the fate of the 48 Iranians captured in Syria and the ongoing conflict in the country.
Ali Akbar Salehi, Iran's foreign minister, is scheduled to visit Turkey Tuesday, and discussions about Syria are expected to be on the agenda.