As the public searches for answers about why suspected gunman Nikolas Cruz opened fire on his classmates and teachers at a high school in Parkland, Florida, his social media history is making one thing clear—the Federal Bureau of Investigation should have seen the warning signs months ago.

"I'm going to be a professional school shooter," A YouTube user named Nikolas Cruz commented on a video on Sept. 24, 2017. The video was posted on the channel "Ben The Bondsman," and the owner, Ben Bennight, immediately took a screenshot and submitted it to the FBI.

Bennight told Buzzfeed News that the bureau was quick to respond, and agents from the Mississippi field office conducted an in-person interview with him the next day.

"They came to my office the next morning and asked me if I knew anything about the person,"Bennight said. "I didn't. They took a copy of the screenshot and that was the last I heard from them."

The next time the FBI contacted Bennight was on Wednesday, just 30 minutes after police in Broward County arrested a suspect with the same name as the YouTube user—Nikolas Cruz—for killing 17 people and injuring at least 15.