Syrian warplanes on Wednesday bombarded a hospital in the rebel-held district of the city of Aleppo, causing dozens of casualties, AFP reported, based on a monitoring group.
"Dozens of people were killed or injured by an air strike on a building in the district of Shaar" in eastern Aleppo, the Syrian Observatory for Human Rights, without giving a precise toll, told AFP.
"The field hospital was badly damaged by the strike," the Britain-based monitoring group added.
Amateur video filmed in Shaar and distributed by the Observatory showed people gathering around the destroyed building, which was reduced to a mountain of grey rubble.
Also in the northern province of Aleppo, the army repelled a rebel attack on a military base at Sheikh Suleiman, 15 miles northwest of the city, killing at least 25 insurgents, the Observatory said, citing rebels.
The area was mined and came under aerial bombardment, it said.
Rebel fighters have besieged the base for several weeks but have now been forced to pull back as forces loyal to President Bashar al-Assad recover ground in northwest Syria, reported AFP.
In contrast, said the report, rebels on Wednesday dragged out the last bodies of soldiers from ruined buildings and gathered the booty of arms and ammunition in the sprawling army garrison of Base 46, also in Aleppo province.
Rebel fighters seized the hilltop base on Sunday.
Defected General Mohammed Ahmed al-Faj, who commanded the assault, hailed the capture as "one of our biggest victories since the start of the revolution" against Assad's regime.
"Nearly 300 regime troops were killed in the fighting," the rebel commander told AFP at the scene. "Some 60 others were taken prisoner, and they will be tried soon."
Base 46 was one of the army's last remaining bases in the area bordering Turkey, which supports the revolt against Assad.
Rebels had aimed to also expel the army from Sheikh Suleiman, as they edge towards declaring the "liberation" from regime hands of northern and northwest Syria.
On Wednesday, the army shelled the southern belt of Damascus and the town of Daraya southwest of the capital, said the Observatory, which relies on a network of activists, doctors and lawyers to compile and verify its data.
According to a preliminary toll compiled by the Observatory, at least 35 people were killed in violence across Syria on Wednesday, among them 16 civilians, five regime troops and 14 rebel fighters.
Ten days ago, Syria's opposition agreed to unite against Assad and elected a cleric as its first leader.
After four days of marathon talks in Qatar, the Syrian National Council finally signed up to a wider, more representative bloc centered on a government-in-waiting, as demanded by Arab and Western states.
Muslim cleric Ahmed al-Khatib, 52, was elected to head the newly formed opposition grouping.
The United States recognized the coalition as the “legitimate representative” of the Syrian people, and France went even further, saying the coalition would be considered by Paris as the sole legitimate representative of the Syrian people.
On Saturday, France invited Syria's new opposition coalition to send an ambassador to Paris.