Haddon Heights High School underwent a brief lockdown on Thursday because of a conflict between two students.
Superintendent Mike Adams says one student was looking for another student and was very upset.
The school, located on 301 Second Avenue in Haddon Heights, NJ, went into a routine Tier 2 lockdown until both students were located and safe. During a Tier 2 lockdown, no one is allowed in or out of the school but teaching continues.
The students were located and the lockdown is now over.
Officials say no weapons were involved in the incident and no one was injured.
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