Assad government raids kill 20 civilians in Syria: Monitor

Air strikes carried out by forces loyal to the government of president Bashar al-Assad killed at least 20 civilians in a rebel-dominated area of northwestern Syria, a monitor said Sunday after raids elsewhere in the country left more than 70 dead.

"The regime's planes have committed another massacre, this time in Jabal al-Zawiya," a mountainous region in the province of Idlib, the Syrian Observatory for Human Rights said of the Saturday bombing.

"Many wounded are in critical condition," said the Britain-based group, which relies on a network of sources on the ground.

The raids came on the same day that barrel bombs dropped by Assad's helicopters killed more than 70 civilians, including children, in the northern province of Aleppo.

Those strikes, which targeted a market in the militant-controlled town of Al-Bab as well as a rebel-held neighbourhood in Aleppo city, prompted an international outcry.

"This is further shocking proof of the horrific and indiscriminate methods the Assad regime is using to kill and injure innocent civilians, including children," said British Foreign Secretary Philip Hammond.

"Our position remains as strong as ever - we will continue to call for a political transition to a future in which Assad has no part," he said.

The government's barrel bombs - crude weapons made of containers packed with explosives - have often struck schools, hospitals, and markets in Syria. 

But Saturday's death toll was among the highest.

UN envoy: 'indiscriminate aerial weapons'

The UN envoy to Syria condemned Assad's bombing of civilian areas as "totally unacceptable."

"The news of aerial bombing by Syrian helicopters on a civilian area of the Aleppo neighbourhood of Al-Shaar deserves the most strong international condemnation," UN envoy Staffan de Mistura said in a statement.

"The use of barrel bombs must stop," he said. "All evidence shows that the overwhelming majority of the civilian victims in the Syrian conflict have been caused by the use of such indiscriminate aerial weapons."

He said it was "totally unacceptable that the Syrian airforce attacks its own territory in an indiscriminate way, killing its own citizens."

After Saturday's barrel bomb attacks on the rebel-held Al-Shaar neighbourhood of Aleppo, victims' bodies were laid out on the streets of the neighbourhood. 

The limp blood-covered hand of one of them protruded from under a blanket, said an AFP correspondent at the scene.

'Revenge against civilians who support the rebellion'

The tactic of carrying out air attacks on built-up areas after battleground losses has become common practise for Syria's regime, which ceded swathes of territory in May.

"The regime has always dropped barrel bombs in this war, but it is intensifying its strikes believing it can compensate for territorial losses," said Observatory head Rami Abdel Rahman.

His group has documented 17,000 barrel bombings by Assad's government since October.

"It is also a kind of revenge against civilians who support the rebellion," said Abdel Rahman. "It's a tactic of scorched earth."

Despite recent losses, Syrian Prime Minister Wael al-Halqi on Sunday pledged the army would "liberate every foot of Syrian territory". 

"The army will defeat terrorist organisations and will hold them accountable for their massacres against the innocent," he said, according to Syria's official news agency SANA.

IS destroys infamous Syria prison

Meanwhile, the Islamic State (IS) group demolished a notorious government prison in the historic Syrian city of Palmyra on Saturday.

The Observatory said IS planted explosives that "largely destroyed" the Palmyra jail, which was for decades a symbol of abuses meted out on opponents of Bashar al-Assad and his father Hafez al-Assad, before him.

Opponents of Assad welcomed on social media the destruction of the long-feared prison at Palmyra, which IS seized 10 days ago after pro-government forces pulled out.  

More than 220,000 people have been killed in Syria since March 2011 demonstrations spiralled into a complex civil war.

Christian fighter beheads IS militant

Meanwhile, a Syrian Christian fighter has beheaded an IS militant to avenge people "executed" by the militants in northeastern Syria, the Observatory said on Friday.

The monitor said the incident took place on Thursday in Hasakeh province, where IS holds large areas of the countryside.

According to the monitor, the Christian fighter, a member of the minority Assyrian community, found the IS militant in the local village of Tal Shamiram.

"He took him prisoner and when he found out he was a member of IS, the Assyrian fighter beheaded him in revenge for abuses committed by the group in the region," Abdel Rahman said.

The Christian was fighting in the ranks of Kurdish forces who earlier this month drove IS out of more than a dozen Assyrian villages IS had captured in Hasakeh.