CO-OP CITY - Police have arrested seven high school students in connection with a violent attack on a classmate from Co-op City Thursday afternoon.

According to witnesses, the attack happened after school hours near Bartow and Baychester avenues, just blocks away from Harry S. Truman High School. They say a group of students attacked a female classmate.

The witnesses say the students planned the attack all day and purposely stayed off of school grounds. Classmates say the fight may have been in response to an altercation that took place earlier in the week.

Cellphone video obtained by News 12 shows a large crowd of boys and girls hovering around as the victim is brutally beaten, dragged on the ground and pulled by her backpack. In the video, the girl is also seen covering her head and face while people are screaming for others to grab her. A photo shows the same girl bleeding from what looks to be a cut on her eyebrow.

Police have not released the names and ages of those arrested, but investigators say all of them attended the same school as the victim. Investigators say that while one girl taken into custody had a knife, they are not sure whether it was used in the fight.

Police have not released the identity or the condition of the victim. They did say she was a freshman at the school.

A security guard at the McDonald's across the street says he has seen students fight before, but nothing of this size. Investigators say there may have been up to 200 students who witnessed the assault.

Police have increased security in the area, but they have not said whether the move is in response to the attack.

Students at Harry S. Truman High School were dismissed early on Friday. One student was taken into custody, though it is unknown if it was in connection with Thursday's fight. Witnesses say it was because he was harassing police.