Wylie High School was locked down Friday morning after a threat was received by the district earlier in the day that a former student was possibly armed and on campus.
Wylie ISD tweeted at about 9:50 a.m. that the lockdown was in effect and that students and staff are safe.
The district told NBC 5 they considered the threat serious and that police were searching for a person who was not a student.
That person was later determined to be at his home and not a threat.
By 10:35 a.m., the lockdown had been lifted and students were seen leaving the building.
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It is not clear how the school was notified of the potential threat or what led the reporting person to believe the threat was imminent.
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