The US State Department says the number of terrorist attacks around the world rose by a third in 2014 compared with the previous year.
In its annual report on terrorism, the State Department says the number of people killed rose by 80%, to nearly 33,000.
It says the sharp increase was largely due to groups like Islamic State in Iraq and Boko Haram in Nigeria.
Attacks in Pakistan, the Philippines, Nepal and Russia decreased.
The deadliest attack was in the Iraqi city of Mosul, when Islamic State killed 670 Shia prisoners.
“Unprecedented” seizure of territory in Iraq and Syria by ISIS, the flow of foreign terrorists joining the group and “lone” offender extremists in the West were major trends in global terrorism in 2014, according to the report.
ISIS specifically sought out religious minorities like Christians and Yazidis in addition to killing Western journalists.
Al-Qaeda was largely fragmented in 2014, but failed governments in countries like Yemen, Syria, Libya, Nigeria and Iraq enabled extremist radicalism.
Terrorist groups used more aggressive tactics in 2014 than years before, such as beheadings and crucifixions.
Boko Haram, operating in northern Nigeria, northern Cameroon and southeast Niger, used stoning, mass murder attacks and kidnapped children en masse.
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