Three children reported a man walking outside on Virginia Tech's campus at 9:09 a.m. Thursday.  The children said that he was holding a gun covered in a cloth.

Virginia Tech, located in Blacksburg, Va., suffered a shooting rampage in April 2007 that left 32 people dead and 25 injured.  

Seung-Hui Cho, a 23-year-old English major, had a history of violent thoughts and behaviors and frightened professors but was allowed to roam free.   The gunman mailed a manifesto of delusional letters, pictures, and video to NBC News prior to the shooting.

The man was described as six-feet tall, white, with light brown hair.  He was wearing a blue and white striped shirt, gray shorts, and brown sandals.  The seemingly suspicious man had no facial hair or glasses.

The university locked down until around 3 p.m.  The following warning was posted on its website: "Person with gun reported near Dietrick. Stay inside. Secure doors. Emergency personnel responding. Call 911 for help."