Video obtained Thursday by 11 News from inside Loch Raven High School shows the moment when SWAT officers arrested a student during a lockdown.

The video shows SWAT officers swarming a third-floor classroom and taking a 14-year-old student away in handcuffs.

Greggor Hines, a senior at Loch Raven High School, shot the video. He said it was otherwise a normal day in his Advanced Placement economics class.

"They came over the intercom and said, 'All teachers lock down,' and there was no indication of a drill, so that was the first kind of indication that something was actually happening," Hines said.

Hines said the teacher looked in the hallway and told a student there to get inside the classroom for safety. Hines said that's protocol in a lockdown. What no one knew was the student who was pulled inside was the student police were looking for because he had a pellet gun.

"We thought this kid's a little bit sketched out. He was out of breath when he came into the classroom, like he was sprinting down the hallway, and he had a backpack on, and he just seemed really on edge. I think he was just scared for the most part," Hines said.

The teacher locked the door and turned the lights off. They heard a helicopter overhead and police going door to door, checking to see if the rooms were locked.

"Based on what happened yesterday (in Florida), it was just a little freakier than a normal lockdown because your thoughts are racing through your head: 'What if there's actually a shooter coming in here?'" Hines said.

Hines said they were getting information about what was going on via social media. When the name of the student with the pellet gun came out, the student who had been pulled into the classroom looked up. The teacher sent the front desk an email and SWAT officers came to the door and arrested the student.

Hines said he is thankful it wasn't a real gun and the situation was resolved peacefully, but it's an experience that has left a lasting impression.

"I think it will stick with me for the rest of my life, and it has definitely changed a little bit of my perspective on things," Hines said.