Story highlights In total 11,774 terrorist attacks in 92 countries took place in 2015 that resulted in more than 28,300 deaths

The report noted that the total number of terrorist attacks in 2015 decreased by 13% when compared to 2014

Washington (CNN) The State Department on Thursday released its annual report on global terrorist activity, listing Iran as the top state sponsor of terrorism and labeling ISIS "the greatest threat globally."

The report also includes statistics on terrorist activity worldwide, and said 11,774 terrorist attacks in 92 countries occurred in 2015.

The department's acting coordinator for counterterrorism, Justin Siberell, briefed reporters Thursday on the report's content, saying the document was used to assess the effectiveness of the effort to combat terrorism and to determine where to best place resources.

On Iran, the report said that country "remained the foremost state sponsor of terrorism in 2015, providing a range of support, including financial, training, and equipment, to groups around the world."

The report also said that Iran was continuing to provide arms and cash to terrorist groups like Hezbollah and Iraqi Shia terrorist groups, including Kata'ib Hizballah (KH). Both groups are designated Foreign Terrorist Organizations in the report.

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