Video shows armed police checking classroom for shooter in Florida

PARKLAND, Florida (KTRK) -- Cellphone video shows the moment police entered a classroom looking for the gunman in Wednesday's deadly shooting at Marjory Stoneman Douglas High School in Florida.

Students can be seen raising their hands above their heads as authorities check the room.

Some of them are visibly shaking.

Suspected shooter Nikolas Cruz was arrested.

The 19-year-old has been charged with 17 counts of premeditated murder in the attack that also injured 23 people.

Raw video: Accused shooter booked into jail overnight

Video shows Florida shooting suspect Nikolas Cruz arriving to the jail.

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