Officials say the incident began as a fight on Wednesday morning at Patriot High School in Nokesville just before the start of class between the victim and a 17-year-old student.
A school resource officer said that during the fight two other students jumped in and struck and kicked the victim, knocking him to the ground where he temporarily lost consciousness.
Police say the accused students continued to strike and kick the victim until they were separated.
The victim was treated for injuries described as non-life threatening.
Police charged two Manassas boys, a 15-year-old and a 17-year-old, with malicious wounding and assault by a mob. A third teen, a 17-year-old boy also from Manassas, has been charged with assault and battery, and assault by mob.
"The safety and security of our students and staff is our highest priority. Any acts of violence that compromise the safety and well-being of students and staff will not be tolerated in our schools," Prince William County Public School officials said in a statement released Wednesday. "We became aware of a fight at Patriot High School that occurred before school started this morning. PWCS took immediate action, including the involvement of the Prince William County Police Department, who is actively investigating this incident. PWCS will apply all appropriate disciplinary action as prescribed by the Code of Behavior. Under the Code of the Behavior, fighting may result in disciplinary consequences up to and including expulsion. Additionally, PWCS will provide support to students and staff members, as needed."
Principal Michael Bishop says at least one student recorded the fight, and that the recording was being distributed.