Intensified wave of raids backing Assad government claim civilian casualties in Homs and Aleppo provinces, sources say.

An intensified wave of Russian air raids backing Syrian government forces have taken a major toll on civilian areas across the provinces of Homs and Aleppo, killing at least 80 people, sources tell Al Jazeera.

Among the sites bombed by Russian warplanes was a field hospital in a southern town in Aleppo on Thursday evening, resulting in numerous deaths and injuries, an Al Jazeera correspondent, reporting from the northern Syrian province, said.

The correspondent said the Russians attacks are also believed to have caused the deaths of all members of two families in Hayan, a town in Aleppo.

Over the last few weeks Russia’s military has carried out many air strikes in a bid to help the Assad government [Reuters]

Furthermore, three members of the opposition armed group, al-Nusra Front, were killed when their vehicle was bombed by a Russian warplane in western Aleppo.

In Homs, scores of people, including women and children, were also reportedly killed after Russian forces bombed many towns and villages, Al Jazeera’s Jalal Abu Sulaiman, reporting from the central Syrian province, said.

He also said that one of the raids struck a place of refuge for civilians in the town of al-Ghantu, “killing 37 people – all from the al-Assaf family”.

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The Syrian Observatory for Human Rights, a UK-based monitoring group, said on Thursday the Russian air strikes hit targets around the town of Talbiseh, Rastan and the villages of Teir Malla, Dar Kabira and Khalidiya, a few miles north of the mainly government-held city of Homs.

It said government forces and fighters from Lebanon’s Shia armed group Hezbollah were involved in the assault.

Activists told Al Jazeera at least 14 civilians were killed in air strikes that targeted an internally displaced shelter in Teir Malla.

Over the last few weeks Russia’s military has carried out many air strikes in a bid to help the government of Bashar al-Assad regain territory after losing the vast majority of the country to opposition groups.

The intensified air raids came as Iran reportedly deployed many more troops to help the Syrian army launch major offensives against rebels.

The Iranian troops arrived in Bassel al-Assad International Airport, near Jableh in Latakia province, the Syrian Observatory said on Thursday.

The airport has of late become a hub for Iranian and Russian forces, where activists confirmed to the Syrian Observatory that thousands of Iranian troops have arrived in the past few weeks.