A 13-year-old boy who was attacked while walking home from school earlier this month in a Philadelphia suburb said Tuesday that he had been bullied since the beginning of classes.

Seven teenagers were in custody Tuesday in connection with the videotaped beating of the teen, authorities said.

Nadin Khoury told HLN's Vinnie Politan said he was glad about the arrests but is concerned about other possible victims.

"Some day they are going to do the same thing to somebody else," the youth said. The group picked on students who were smaller than them, Nadin said.

Six of the youths were arrested Monday at an alternative program at Upper Darby High School, Upper Darby police Lt. Thomas Sharp said. A seventh, who was absent Monday, was arrested Tuesday, he said. Khoury and all seven suspects attended the alternative program, called the Opportunity Center.

The attack took place January 11, Sharp said. The school district's security force heard chatter about the incident among students and notified police, he said.

A video taken on the cell phone of one of the suspects shows the boy being kicked, dragged through the snow and stuffed into a tree, then hung from his jacket on a tall wrought-iron fence. On the video, the boy can be heard screaming as his attackers laugh.

Asked if police know what prompted the attack, Sharp told CNN, "bullying ... just picking on somebody."

Khourys mother, Rebecca, told HLN, "I could not even believe what I was seeing on the video."

"He did not deserve this," she said. This is not right. This is wrong."

"It was seven against one," said Michael Chitwood, police superintendent for Upper Darby Township. "It was a wolf pack."

Chitwood told HLN "this is not a joke" and that Khoury could have been killed or seriously injured when he was put on the fence.

"Bullying has always been amongst us, but these thugs videotape themselves and then go on social network sites and become heroes," he said earlier Tuesday. "These kids, these thugs, these criminals have a sense of empowerment. The mentality is idiotic, but it helps us solve crimes."

Police confiscated the video before it was posted to any networking sites, he said.

"It (videotaping) changes the whole dynamic," he said. "It validates what happened."

The suspects range in age from 13 to 17 and will face juvenile charges of kidnapping, aggravated assault, criminal restraint, terroristic threats, reckless endangering of another person and conspiracy, Chitwood said.

Nadin Khoury told CNN affiliate WPVI that he "tried to get out, tried to leave, tried to escape, tried to get out (of) the tree and run away, but even when I did that -- got out of the tree the first time -- they attacked me and they caught me again."

The boy was not seriously injured, Sharp said.

Rebecca Khoury told WPVI that the family came to America from Liberia in 2000 in search of a better life.

"This is the land full of milk and honey," she told the station. "We all came here for the honey. ... This is crazy, I mean, there's nothing you can do to protect your own kids."

"Bullying is terrorizing people," Chitwood said. "It's a crime. That's why I took (the suspects) out of school in handcuffs. It's not a joke."

The beating reportedly occurred at an apartment complex, and police said at least one person walked by and did nothing, despite the boy's calls for help. "No one called 911," police Capt. George Rhoades told WPVI.

"I've been a cop for 47 years," Chitwood said. "The criminal element out there is more brazen than it's ever been. The world of technology has empowered them, and I don't say that in a positive way."

Five of the seven suspects have no criminal records, he said. Of the two that do, one -- a 14-year-old -- has two previous assault charges.

All the suspects were being held at the Lima Juvenile Detention Center in Lima, Pennsylvania, about 10 miles west of Upper Darby, he said. A detention hearing will be held in the next few days.

In a phone message to parents Monday night, Upper Darby School District Superintendent Louis DeVlieger praised the efforts of teachers, school district security and police in the case, saying they show "how seriously we take the safety and well-being of our students even when an event takes place off campus on the way home from school."

Rebecca Khoury applauded the response from the school.

In the statement, obtained by CNN, DeVlieger said the alternative school program is "for students who have exhibited poor decisions in the past and are therefore removed from the high school to protect the regular high school student population."

The program has been successful in helping many students rehabilitate, he said, but "apparently the students taken by the police today chose to continue to make bad decisions that ultimately resulted in their arrests and removal from school."

"Today we had 12,134 great kids in our district and six that gave us great concern," he said. "The good sure outweighs the bad in this district by a large margin. Remember that each and every day."

Upper Darby is just west of Philadelphia.