Both attend Stem Launch in the Adams 12 school district.
According to Thornton police, they responded to the school around 10 a.m. Tuesday after the school contacted them. They did not say where in the school the assault happened.
Police say the 14-year-old male suspect was taken into custody.
The names of the boys have not been released.
Click here to the letter to parents from STEM Launch Principal Diana Gamboa.
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