Cruz: 'Dems' Reaction to Any Tragedy Is to Politicize,' Push Gun Control

The FBI said Thursday it investigated a threatening YouTube comment which is believed to have been made by the gunman who killed 17 people at a Florida high school. 

"I'm going to be a professional school shooter," a commenter wrote last year on YouTube under the name "Nikolas Cruz." 

FBI Special Agent Rob Lasky said at a news conference that the comment was flagged to the agency, but the person behind the comment could not be located. 

Lasky said agents conducted "database reviews [and] checks but was unable to further identify the person that made the comment."

The YouTube comment was left on a video about the 1966 University of Texas clock tower sniper, who killed 18 people. 

Nikolas Cruz, 19, was arrested Wednesday near Marjory Stoneman Douglas High School in Parkland, where he is alleged to have opened fire with an AR-15 rifle after pulling the fire alarm. 

Cruz, an avowed gun enthusiast, had been expelled from the high school and students have said they were not surprised to learn he carried out the shooting. 

Watch the comments above. 

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