Although Islamic State is losing fighters and territory in Iraq and Syria, it remained the world's deadliest militant organisation last year, according to a report from the University of Maryland.
Islamic State operatives carried out more than 1,400 attacks last year and killed more than 7,000 people, a roughly 20 per cent increase over 2015, according to the university's Global Terrorism Database. The increase occurred even as overall militant attacks worldwide and resulting deaths fell by about 10 per cent in 2016.
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Senior US counterterrorism officials said the latest attacks fit a pattern in which IS adapted to significant battlefield setbacks in Syria and Iraq, where its control of territory peaked in August 2014, by intensifying calls for attacks by individuals or small groups using whatever means possible.
In addition to violence tied to IS' core group in Iraq and Syria, other groups affiliated with it carried out more than 950 attacks last year that killed nearly 3,000 people, the university report said.
In 2016, four additional groups pledged allegiance to Islamic State. Affiliates in Bangladesh, Yemen, Libya, Afghanistan-Pakistan and the Philippines killed significantly more people and executed more attacks than in the previous year, the report said.
Most of the affiliates were already engaged in conflicts before allying with Islamic State, said a senior State Department official. Islamic State "was able to manipulate and hijack" them, said the official, speaking on condition of anonymity.
The group also has issued more calls for its followers to carry out lone-wolf attacks such as those that occurred in recent years in Orlando, Florida, San Bernardino, California, London and Manchester and Nice.
"During this same time period, we (also) saw an increase in the number of individual assailants," said Erin Miller, author of the University of Maryland study.