ISIS kills dozens execution-style in Syria

In what is believed to be the group's largest mass killing of 2017, a monitoring group says ISIS killed dozens execution-style on Wednesday.

The terror organization carried out 33 killings near Syria's strategic city of Deir Ezzor on Wednesday morning, according to the Syrian Observatory for Human Rights.

The monitoring group -- who operates out of London -- called the mass killing "the largest execution operation carried out by the Islamic State organization in 2017."

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Reports describe victims who were "killed by sharp tools" as between the ages of 18 and 25. Whether those killed were rebels, Syrian government officials or militia allies remains unknown.

The terrorist organization also killed at least 22 people in Iraq on Wednesday, when they opened fire on civilians and police in the city of Tikrit. They wounded an additional 31 people before blowing themselves up.