17 Students Killed In US High School Shooting

At least 17 people were killed when a teen opened fire with a semiautomatic rifle at a high school in Parkland, Florida, on Wednesday afternoon, officials said.

Fourteen others were wounded, five of whom suffering life-threatening injuries, hospital officials said.

Authorities said the suspect, identified as 19-year-old Nikolas Cruz, concealed himself in the crowd fleeing Marjory Stoneman Douglas High School. He was arrested in nearby Coral Springs and later charged with 17 counts of premeditated murder.

Cruz had recently been expelled from Douglas for disciplinary reasons and was enrolled elsewhere in the district, Broward County schools Superintendent Robert Runcie said. He took an Uber to campus on Wednesday, Runcie told NBC News.

The gunman was believed to have been armed with an AR-15-style semiautomatic rifle and multiple magazines, said Broward County Sheriff Scott Israel. It was unclear whether he had any other weapons, Israel said.

Cruz was taken into custody off campus about an hour after he "committed this horrific, detestable act," said Israel, who added investigators were reviewing social media postings that he described as "very disturbing." The suspect was treated for "labored breathing" as a precaution but was later released from the hospital, according to officials.

"You come to the conclusion this is just absolutely pure evil," said Florida Gov. Rick Scott, his hands clutched over his chest.

Scott, a Republican whom the National Rifle Association's Political Victory Fund gave an "A+" rating, didn't directly answer reporters' questions about how the gunman was able to obtain a semiautomatic rifle.

The FBI was alerted six months ago after a YouTube user named "Nikolas Cruz" posted a comment stating "I'm going to be a professional school shooter" on the video site, BuzzFeed reported early Thursday.

Cruz's mother died in early November and he had been staying with a local family — whose son is a junior at Douglas, the family's attorney told NBC Miami.

"He lived here without any concerns or issues for almost three months and they are shocked and horrified by the allegations being made," lawyer Jim Lewis said, adding that his clients are fully cooperating with investigators.