Two people, including a Virginia Tech police officer, were dead after a shooting incident on Virginia Tech's campus in Blacksburg today, the university said.

A CNN report says that witnesses saw the police officer being shot during a traffic stop on campus, and the second victim was found dead at a nearby parking lot toward which the gunman had been seen fleeing. The status of the shooter was not immediately known, and the campus was on lockdown Thursday afternoon, the report said. All classes have been cancelled for the day.

The incident comes more than four years after a shooting spree in which a Virginia Tech student, 23-year-old Cho Seung-Hui, shot dead 32 people on the campus before killing himself in April 2007.

The shooting also came the same day as Virginia Tech was appealing a $55,000 fine by the U.S. Education Department in connection with the university's response to the 2007 incident.