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.
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By 10:35 a.m., the lockdown had been lifted and students were seen leaving the building.
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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