A report released by IHS Janes' Terrorism and Insurgency Center stated that despite losing ground in Iraq and being targeted by US-led coalition airstrikes in both Iraq and Syria, the extremist group managed to carry out 935 attacks between October 1 and December 31, 2015.
Russian warplanes began flying their first sorties in the Syria during the last week of September.
Russia's initial stance was that its planes were targeting the Islamic State, but reports soon emerged that the airstrikes were helping prop up Syrian President Bashar al-Assad's beleaguered forces.
The Islamic State has been taking advantage of Russian airstrikes in Syria, using the newfound air cover to manoeuvre and reposition fighters, the report was quoted as saying by The Washington Post.
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Despite the increase in attacks, the average fatalities per attack -- approximately three -- remained consistent with the past year.
Additionally, the Islamic State's attacks also "continued to track above the average recorded over the preceding 12 months", the report said.
Number of attacks, however, does not equate to the group's ability to hold territory. The extremist group has lost ground in both northern Syria and Iraq, though it has retained the ability to mount effective counter-attacks and raids in both areas, it said.
In London last week, the spokesman for the US-led operation against the Islamic State, Army Colonel Steve Warren, told reporters that the Islamic State is now in a "defensive crouch" in Iraq and Syria.
Russia began its air campaign in Syria under a shroud of secrecy, funnelling supplies and equipment into a Syrian airbase in Latakia province for more than a month before its first strike aircraft started operating.
Russian planes, in conjunction with detachments of Russian artillery and troops, began pounding areas held by opposition forces and al-Qaeda's Syrian affiliate Jabhat al-Nusra.