The number of suicide bombings in the world nearly doubled in 2014, the Israeli left-leaning daily Haaretz reported on Sunday, citing an Israeli think tank report.

According to the Haaretz , a yet-to-published (at least in English) report by the Tel-Aviv based Institute for National Security Studies found that suicide bombings worldwide increased 94 percent in 2014 from a year earlier. There were 592 suicide attacks last year compared with 305 attacks in 2013, the think tank-- which is affiliated with Tel Aviv University-- finds in the report. These attacks killed some 3,400 people in 2014, compared to the 2,200 people who were killed in suicide attacks back in 2013.

The researchers note that their numbers are conservative estimates because they required at least two sources for each bombing before concluding it was a suicide attack. According to the newspaper report, the researchers said finding reliable information was particular difficult in Syria.

Suicide attacks rose most sharply in Iraq in 2014, which saw 271 such attacks compared to just 91 the year prior. Yemen, Lebanon and Libya also saw an increase in the number of suicide attacks, ranging from 10 more attacks in Yemen compared to just one more attack in Libya. The researchers found that suicide attacks in Syria stayed remarkably consistent from 2013 to 2014, with 41 such bombings in both of those years.

Suicide attacks across the Middle East more than doubled in 2014, increasing from 163 in 2013 to 370 attacks last year. The number of fatalities in these suicide attacks in the Middle East also surged from 1,950 to 2,750.

The largest factor behind the increased appeared to be the rise of the Islamic State of Iraq and al-Sham in the Iraqi state. Although the researchers said the group rarely claimed responsibility for the suicide operations, they conclude that they were behind the bulk of the attacks. The overwhelming majority of these attacks (71 percent) targeted Iraqi security forces, and many of them were carried out by foreigners, the INSS report found.

Overall, 45 percent of suicide attacks in 2014 occurred in Iraq. This should not be overly surprising as Iraq has often been in a league of its own when it comes to suicide attacks. In fact, according to data from the Chicago Project on Security and Terrorism, roughly half of all suicide attacks globally between 2004 and 2009 occurred in Iraq. Furthermore, number of suicide attacks in Iraq peaked at over 300 in 2007, the exact time that sectarian tensions were at their highest in that country. As sectarianism died down over the ensuring years, so did suicide bombings in the country.

Zachary Keck is Managing Editor of The National Interest. You can follow him on Twitter: @ZacharyKeck .

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