LOS ANGELES (CBSLA.com) — A Hacienda Heights high school was placed on lockdown Monday after a student reported a threatening note that was found in a textbook.

School officials initiated a school-wide lockdown at Glen A. Wilson High School after administrators heard the report around 9:20 a.m., according to a statement from Hacienda La Puente Unified School District Supt. Cynthia Parulan-Colfer.

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Deputies arrived on campus a short time later and a campus-wide search was being conducted, Parulan-Colfer said.

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The lockdown was lifted around 1:50 p.m. after it was determined that the students and faculty were safe and that there was no threat to the campus following a “thorough search of the campus”.

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In a statement, Parulan-Colfer said: “We know that this is a stressful situation for everyone involved and we apologize and share in the anxiety that we know this creates for parents. Our commitment is to providing parents and the community with as much information as quickly and accurately as possible.”