Authorities were contacted by NOVA Academy Charter School Monday night after the suspect allegedly sent threatening emails to his ex-girlfriend, who is also a student at the school.
"This ex-girlfriend had received approximately 14 emails from the suspect, talking about his desire to kill students," said Santa Ana Police Cpl. Anthony Bertagna.
While the teen did not threaten the ex-girlfriend, he said that he was going to be shooting at the school and recruit other students to help him carry his plan out, police said. He also apparently told another female student about his plans.
The high school sophomore told his ex-girlfriend in the email that he was tired of being bullied.
Both girls reported the threats to the principal. The teen was taken into custody and placed at juvenile hall while police continue to investigate the incident. Police say it is not clear if the student approached other students to try to recruit them to carry out the shooting. Detectives are also investigating whether the student had access to weapons.
The teenager, described as a good student, remains in juvenile hall.
The school said it is still taking steps to ensure students are safe. An armed guard will be on campus from 5 a.m. to 10 p.m. Monday through Friday until at least April 11, when students begin spring break.