Five students were injured in a shooting Tuesday afternoon at Wilmer-Hutchins High School in southeast Dallas when a 17-year-old allegedly snuck into the school and fired “indiscriminately,” according to a state affidavit for the suspect’s arrest warrant.

The injured, aged 15 to 18, were taken to a hospital for treatment, with their injuries ranging from non-life-threatening to serious, Dallas Fire-Rescue spokesperson Jason Evans told CNN affiliate WFAA.

The Dallas Independent School District Police initially said four students were injured, but the affidavit later increased the number of victims to five.

The teen is being held at a Dallas County jail on a first-degree aggravated assault mass shooting charge, a felony, with a $600,000 bond, according to county records. It is unclear if he has obtained an attorney or made an initial court appearance.

The shooting began just after 1 p.m., and an officer at the school responded within two minutes, followed by officers from numerous agencies, Stephanie Elizalde, superintendent of the Dallas Independent School District, said at a Tuesday news conference.

Surveillance video circulating on social media appears to show a chaotic scene from Tuesday’s shooting.

What begins as a seemingly normal school day at Wilmer Hutchins High School takes a horrifying turn as a shooter appears on screen and students begin to scatter.

At one point, the video shows the shooter pointing a gun at a lone student on the ground before fleeing down a hallway out of the camera frame.

The footage matches information included in an affidavit obtained by CNN, but CNN has not independently verified the video.

According to the affidavit, surveillance footage reviewed by police showed an unidentified student letting the suspect into the school through an unsecured door at approximately 1:03 p.m.

The suspect then brandished a firearm and began firing at students, striking five, according to the footage described in the affidavit. The suspect approached one student who was not able to run and “appeared to take a point-blank shot,” the affidavit said.

When sent a copy of the footage, Dallas Independent School District told CNN it would not be able to confirm its validity.

CNN has reached out to Dallas Police for comment on the footage.

Authorities did not provide any information on a motive for the shooting, as the investigation was fluid, Christina Smith, the school district’s assistant police chief, said at the news conference.

“This is just becoming way too familiar, and it should not be familiar,” Elizalde said. Classes at the high school have been canceled for the rest of the week, she said.

The shooting occurred nearly a year after a different incident at the high school left one student injured, according to WFAA. In the April 2024 incident, a student brought a handgun into the school, bypassing metal detectors and a clear-bag policy, the outlet reported, citing what officials said at the time.

Following Tuesday’s shooting, Wilmer-Hutchins Elementary School, located adjacent to the high school, was put on lockdown as a precaution due to its proximity, though it was not in danger, Elizalde said. The elementary school will hold classes on Wednesday and Thursday with a heightened police presence, she added.

Texas Gov. Greg Abbott called Elizalde to receive a status report and offer any necessary state resources, the superintendent said. All evacuated students were subsequently reunified with their parents and guardians, she added.

“Our hearts go out to the victims of this senseless act of violence at Wilmer-Hutchins High School,” Abbott said in a release.

“I offered to support the school district families, students, and staff and to provide law enforcement with the tools they need to arrest the criminals involved and bring them to justice,” he said.

CNN’s Lex Harvey contributed reporting.

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