An 18-year-old student was stabbed multiple times by a 17-year-old student at a high school in upstate New York on Monday.

Police say that at around 10:50 a.m. at Proctor High School in Utica, New York, teachers were notified of a physical altercation occurring between two students in the first-floor hallway.

When they arrived, they saw a 17-year-old student allegedly stabbing an 18-year-old student multiple times. “Without regard for their safety,” the teachers intervened, removed the knife from the suspect, and held him until security could help separate the two parties. He was held in a secure area until police arrived.

A bystander recorded the assault on video.

Graphic Content: Viewer Discretion Advised 

The victim suffered multiple stab wounds to his back and hands and was given immediate medical care by school nurses before being taken to the hospital. His injuries are non-life threatening.

While the Utica Police Department is still investigating the incident, WKTV reported that the 17-year-old suspect is facing attempted assault and criminal possession of a weapon charge.

Police are asking any students or bystanders who witnessed, recorded, or if they have any relevant information regarding the violent assault to come forward with evidence to school administrators or investigators. Counseling services are also being offered to any student who is affected by the incident.

According to WKTV, the Utica City School District installed metal security detectors in each of its schools at the beginning of the school year, raising questions as to how the deadly weapon evaded detection.

Acting Superintendent Brian Nolan told the outlet that the district and police are investigating how this could have occurred.

“[We’re] looking at the metal detecting systems themselves, we’re looking at the calibration, the police are interviewing the assailant and trying to get information from him on how the weapon was brought into the school,” Nolan said.

The high school campus will remain closed for the rest of the week, as students will not be able to exit the building during lunch or free periods. The protocol will be reevaluated next week.

The Utica police will also be increasing their numbers on the high school grounds.

“We understand that many questions will be raised throughout this process, and we will be as transparent with the answers as we can. The safety and security of our students and staff remains the number one priority, and we will never stop striving to ensure that happens,” said the police and school district in a joint statement.

You can follow Ethan Letkeman on Twitter at @EthanLetkeman.