A YouTube user who reportedly has the same name as the suspected Florida gunman was investigated by the FBI for a comment boasting about plans to shoot up a school, the agency said Thursday.
The FBI was alerted to the comment but failed to identify the user, Robert Lasky, the FBI agent in charge of the Miami division, said at a news conference.
The suspect in the shooting at Marjory Stoneman Douglas High School, identified as 19-year-old Nikolas Cruz, has been charged with 17 counts of premeditated murder, officials said Thursday.
A user named “nikolas cruz” wrote “I’m going to be a professional school shooter” in a comment posted last September under a video uploaded by a Mississippi bail bondsman, BuzzFeed News reported. NBC News has not confirmed that information.
Cruz concealed himself in the crowd fleeing the school following the massacre on Wednesday afternoon, authorities said.
He was believed to have been armed with an AR-15-style semi-automatic rifle and multiple magazines, Broward County Sheriff Scott Israel said. It was unclear whether he had any other weapons.
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The families of all the victims have been notified and a full list will be released, Israel said at the news conference Thursday.
Cruz had recently been expelled from the school for disciplinary reasons and was enrolled elsewhere in the district, said Broward County schools Superintendent Robert Runcie.
Investigators were reviewing social media posts from Cruz that Israel, the county sheriff, described as “very disturbing.”
The gunfire began outside the school and continued inside, where 12 of the victims were killed, Israel said.
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There was no indication the gunman had an accomplice or accomplices, federal and local authorities told NBC News.
The school had gone through a fire drill earlier in the day, several students told NBC News. They said the fire alarm sounded again just before the shots were heard.
This is a developing story. Refresh for updates.