Yet another video shows 18 white cloth bundles holding the remains of those killed.
Other videos from the city of Aleppo show the aftermath of an airstrike on a mosque late Wednesday. While some men carry away bodies, others work to dig out a survivor whose legs are buried in debris.
Activist claims and videos cannot be independently verified due to restrictions on reporting in Syria. But all videos corresponded to activist reports and appeared to have been filmed where they said they were.
The footage provides a window into the carnage wrought by the Syrian military's increasing reliance on airstrikes to fight rebels waging a harsh civil war to topple President Bashar Assad.
Rights groups say the airstrikes often hit civilian areas. And this week, Human Rights Watch accused Syria of using cluster munitions, which the New York-based group says endanger civilians.
The regime contends that it is fighting terrorists backed by foreign powers who seek to destroy Syria. It also denied using cluster munitions.
An Aleppo-based activist who gave his name as Abu Raed said men were arriving for Wednesday evening prayers when a fighter jet dropped a bomb on the Light of the Martyrs Mosque in the Shaar neighborhood.
The blast destroyed a room used for ritual washing and part of the prayer hall itself, he said via Skype.
He said at least 10 people had been killed, though the number could be higher, either because bodies were still trapped in the rubble or because people were buried before being recorded.
"There were people who took the dead and wounded away before the cameras showed up," he said.
Videos that activists said were shot soon after the attack show a block-wide expanse of rubble surrounded by buildings whose facades had been blown off. Men scour the rubble, occasionally finding bodies and carrying them off.
Rebels and regime forces have been clashing for months in Aleppo, Syria's largest city.
Regime aircraft also pounded Maaret al-Numan and surrounding areas on both days. The area has seen heavy fighting since rebels seized the city last week.
One strike hit a neighborhood near the rebel field hospital on Thursday in Maaret al-Numan, Yassin said via Skype.
He said it was too early to know how many people had been killed. A video posted online later showed 18 white cloth bundles activist said contained the remains of those killed.
Airstrikes also hit three nearby villages on Wednesday, killing 15 people, said activist Fadi Yassin. Nine of those were in Kafar Nubul, while others died in the villages of Kafrouma and Hass.
Rebel brigades from the surrounding area have poured in to defend the town, which stands along the main highway linking Aleppo to other large Syrian cities further south.
Online videos have shown them firing mortars at regime troops, and they claimed to have shot down a government helicopter on Wednesday.