A U.N. report released Tuesday says at least 18,802 civilians in Iraq were killed and another 36,245 wounded between Jan. 1, 2014 and Oct. 31, 2015.

The reports calls the civilian death toll "staggering" and details killings by the Islamic State group including by shooting, beheading, bulldozing, burning alive and throwing people off of buildings.

The report also stated that the Islamic State group is believed to currently be holding approximately 3,500 people, predominantly women and children from the country's Yezidi minority, captive as slaves.

IS swept across northern and western Iraq in the summer of 2014 plunging the country into its worst political and security crisis since the withdrawal of U.S. troops in 2011.