BROOMFIELD, Colo. (AP/CBS4) – Police say a 14-year-old girl was stabbed at a school in Broomfield and a 14-year-old boy was detained.

Authorities say the girl was stabbed Thursday at approximately 11:30 a.m. at Aspen Creek K-8 School and then airlifted to a hospital.

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The stabbing occurred during recess. Eighth-graders say a joke gone too far may be what led to the stabbing.

“He’s been depressed for quite a while, and they just pushed it too far and he snapped,” student Skyler Coleman said.

The scene Thursday morning (credit: Glenn McReynolds)

The scene Thursday morning (credit: Glenn McReynolds)

Coleman was standing on the playground when he saw a male student, a fellow eighth-grader, become offended by a joke a female student was telling.

“He reached into his binder and I think one of the kids knew what it was so he tried stopping him,” Coleman said.

The student pulled what Coleman described as a kitchen steak knife out of his backpack.

“He went and stabbed one of the girls and then the other kid grabs the knife from his hand and then a teacher comes and holds him down,” Coleman said.

One eighth grader told CBS4 that the suspect was acting strangely.

“He was shaking really badly, his hair was in his face, he had his head down and was walking alone and I just got the feeling that something was wrong with him today,” said student Bryce.

Police say she was stabbed in the back. The school went into immediate lockout, not letting outsiders in.

The student being airlifted to the hospital (credit: North Metro Fire Department)

The student being airlifted to the hospital (credit: North Metro Fire Department)

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It’s really scary and so close to home,” said mother Jaime Smith, whose son goes to school there.

When Smith asked her son, “How were the kids in your classroom?” he replied, “Some were crying.”

North Metro Fire Rescue spokeswoman Sara Farris wouldn’t comment on the extent of the girl’s injuries. She says the girl was airlifted because it was the quickest way to get her to a trauma unit, given traffic and other considerations.

The student being airlifted to the hospital (credit: North Metro Fire Department)

The student being airlifted to the hospital (credit: North Metro Fire Department)

Police say the attack appears to be an isolated incident and there’s no reason to believe there’s any additional threat to the school, where both teens are students.

The school remained in session on lockout with restricted access.

“Nobody wants to have a day at school like this anywhere, anytime,” Boulder Valley School District spokesperson Briggs Gamblin said.

After the stabbing the school reached out to parents three times.

Smith said that eased some of her concerns, “A lot of parents said they have really good procedures down here.”

School will resume on Friday as regularly scheduled.

Note To Parents From Aspen Creek K-8 School

Aspen Creek K-8 will follow a regular school schedule on Friday. Counseling support will be available to students throughout the school day. Should your child need additional support, please contact Kim Coringrato at 720-561-8010.

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