The Syrian Observatory for Human Rights (SOHR) reported that Damascus planes had carried out almost 40 bombings in various parts of Idlib and Hama provinces, strongholds of opposing armed groups.
Nine civil, including two children, died in Ariha town of Idlib and 28 were injured in the bombing by government planes, the SOHR was cited as saying by Efe news.
Another child was killed in air strikes outside Kafr Auid, also in Idlib, the last region controlled by rebel and Islamist groups.
According to the SOHR, Russian planes carried out bombings in Hama. It further said that the Syrian Army conducted artillery and helicopter attacks in Aleppo province, neighbouring Hama and Idlib, where there were still rebel fighters present.
An anonymous Syrian military source told Efe news that the Syrian Army attacked "intensely" with artillery and missiles, and with air support from its own government and Russia, the north and northwest of Hama in the past 48 hours.
Troops are preparing to advance on the ground towards the areas in the hands of the armed factions, in particular the Islamist group Army of Al Aza, the source added.
At the end of April, the violence picked up and this week there has been a considerable increase in Syrian and Russian air and land attacks, in addition to the launching of rockets by the insurgents in response.
UN High Commissioner for Human Rights Michelle Bachelet on Friday denounced that 103 people, including 26 children, lost their lives from attacks by the Syrian Army and its allies in the past 10 days in Idlib and Aleppo.
( With inputs from IANS )