The air strikes targeted areas controlled by the Islamic State (IS) group in Aleppo and al-Raqqa, the de facto capital of the IS, according to the Syrian Observatory for Human Rights.
Tens of people have also been wounded, some in critical conditions, according to the Observatory report.
Early on Tuesday, the watchdog said that warplanes, believed to be Russians, carried out an air strike on the IS-held town of Maskaneh in the eastern countryside of Aleppo, targeting a marketplace and leaving at least 12 people killed.
The Russian air raids have started targeting IS-controlled areas in Syria late in September. The Russians and the Syrian government say the air strikes precisely target militant groups, not civilians, as the Russians uses sophisticated reconnaissance equipment before carrying out the attacks.
Air strikes kill 34 people in IS-controlled Syrian areas
18 December 2015
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At least 34 people were killed over the past 24 hours in the Syrian provinces of al-Raqqa and Aleppo by air strikes believed to be Russian, a monitor group reported Friday.
