CUMMING — Forsyth Central High School was put on lockdown Thursday morning after a 16-year-old from Lumpkin County was discovered trespassing on campus, authorities said.

The teenager reportedly had friends who attend Central, and was apprehended a short time later near the campus on Tribble Gap Road.

Robin Regan, a spokesman with Forsyth County Sheriff’s Office, would confirm only that one person had been taken into custody. Citing the visitor’s age, he declined to release additional details.

According to a statement from Central Principal Mitch Young, the school was in a “code yellow lockdown for about 25 minutes.” He added that “parents with questions or concerns could contact administrators.”

A code yellow is a preventative lockdown where the school is on high alert status, according to the school district.

During a code yellow, teachers continue with lessons, but classes do not change and students are told to enter the nearest supervised location and remain there until further instructions from teacher in charge.

Jennifer Caracciolo, a spokeswoman for the school district, said the system would not be releasing any more information since it is considered a criminal investigation.