Russia says its military forces in Syria have carried out 64 combat sorties against 55 targets over the last 24 hours.
A Defense Ministry spokesman said in Moscow on October 10 that Moscow's military campaign in Syria has been intensified because a large number of targets have been identified by aerial reconnaissance.
Moscow says its air strikes are targeting assets of the extremist Islamic State (IS) organization.
The independent Syrian Observatory for Human Rights said on October 10 that Russian jets had carried out strikes in western Syria.
The organization said there is a minimal Islamic State presence in the areas where the air strikes were carried out.
Syrian opposition figures and Western governments have said Russia is using its campaign to strengthen the government of Syrian President Bashar al-Assad rather than to combat extremism.
The observatory also reported a large explosion on the outskirts of the town of Al-Bab, which is an IS stronghold.
The group said it was unclear what had caused the explosion, which occurred at a building used by the IS to store munitions.
On October 9, the NGO Human Rights Watch said at least 17 civilians were killed in the Homs area by Russian air strikes earlier this month and called for an investigation.