A 19-year-old former student opened fire at a high school in Florida on Wednesday, killing at least 17 people, a local police official said.

The police identified the gunman as Nikolas Cruz and took him into custody after the shooting at Marjory Stoneman Douglas High School in Parkland, which is about 70 kilometers north of Miami.

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Broward County Sheriff Scott Israel told reporters the shooter had been expelled from the school for disciplinary reasons. Israel said that the police began to dissect the suspect's websites and social media he was on, adding some of the content was "disturbing."

Calling the incident "catastrophic," Israel added that 12 of the victims were killed inside the school building, two others just outside, one more on the street and two others died of their injuries at a hospital.

The White House said President Donald Trump is monitoring the situation.

"The president has been made aware of the school shooting in Florida," deputy press secretary Lindsay Walters said in a statement. "We are monitoring the situation. Our thoughts and prayers are with those affected."

Despite a number of school shootings in recent years, efforts to pass gun control legislation in the country remain stalled due to opposition from those arguing that gun rights are protected by the U.S. Constitution.

On Jan. 23, two students were killed at a high school in Benton, Kentucky after a 15-year-old student opened fire.

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