A new study published on December 11 says violence by Islamist militants around the world in November killed a total of 5,042 people.
The joint report by the BBC World Service and the International Center for the Study of Radicalization (ICSR) at King's College London says there were 664 attacks in 14 countries during the month.
The worst-hit country was Iraq, where one-third of the deaths occurred. It was followed by Nigeria, Afghanistan and Syria.
The report says Islamic State militants in Iraq and Syria were responsible for about half of the violence, killing 2,206 people in 308 attacks.
It says that 60 percent of the killing was done by groups with no formal association with Al-Qaeda, pointing to "an increasingly ambitious, complex, sophisticated and far-reaching movement."
The reports says it "seems obvious that the jihadist movement" is "stronger than ever" and that countering it will be a "generational" challenge.
Based on reporting by BBC and AFP