Associated Press - November 4, 2009 7:44 AM ET

TEMPE, Ariz. (AP) - Tempe police are searching for a student at McClintock High School who apparently brought a loaded firearm on campus.

Police say 15-year-old Larue Jaquile (Rue-Rue) Johnson and another male student had an off-campus altercation last week and the teen made additional threats to the same student Monday at school.

Security employees were escorting Johnson to the school office when he fled the campus, leaving his backpack behind which they say contained a loaded firearm.

School administrators and school security immediately placed the campus under modified lockdown.

The school sent home a letter with the students to inform parents and guardians about the incident.

Police say the Johnson's whereabouts are unknown and they want to speak with him about the incident although he hasn't been charged with a crime.

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