UPDATED 03/16/12 12:09 p.m.

CARPENTERSVILLE, Ill. (CBS) — Dundee-Crown High School in Carpentersville was placed on lockdown Friday amid reports of a man with a gun.

A suspect, a senior at the school who was not on campus at the time of the threat, was in custody as of 12:05 p.m. Police said the suspect surrendered at his home.

The school, at 1500 Kings Rd. in the northwest suburb, was on lockdown as of 11:30 a.m., Carpentersville police Detective Pete Bone told WBBM Newsradio’s Nancy Harty. The students were kept inside classrooms while police investigated.

Police received the call about the armed man around 11:10 a.m.

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