A Facebook post warning that a gun may be brought on the campus of Robert E. Lee High School has led to an investigation by Tyler Independent School police and officials.

The school district has increased security and will continue to investigate, but at this time the claims have been unsubstantiated according to Tyler School District officials.

Lee school administrators learned of the Facebook post this morning.

UPDATE: Robert E. Lee has not been on lockdown today, and the Tyler ISD automated phone system has started making calls to parents to assure them their children are safe.