Virginia Tech is on lockdown after reports of shots fired on campus on Dec. 8, 2011. (Photo: WDBJ)

BLACKSBURG, Va - A police officer and another person were shot at Virginia Tech on Thursday morning and officials warned everyone to seek shelter while an armed suspect was at large on the campus where 33 people died in 2007 in the deadliest mass shooting in modern US history.

A news release from the school says the police officer had pulled someone over in what was a routine traffic stop Thursday. The officer was shot and killed during the traffic stop.

Witnesses told police the shooter ran toward a parking lot on campus. A second person was found dead in that parking lot.

A campus-wide alert tells students and faculty to stay inside and lock doors.

The suspect is described as a white male wearing gray sweat pants, gray hat with neon green brim, maroon hoodie and backpack.

A student gunman killed 32 students and faculty and then shot himself on the campus in 2007.

The shooting came the same day as Virginia Tech was appealing a $55,000 fine by the US Education Department in connection with the university's response to the 2007 rampage, when a student gunman killed 32 students and faculty and then shot himself.

In the deadliest mass shooting in US history, 33 people, including the mentally ill gunman, were killed on the Virginia Tech campus on April 16, 2007. The massacre in a classroom building began at 9:40 am when Seung-Hui Cho chained the doors and killed dozens before committing suicide.

Armed police officers search the Virginia Tech campus near the Squires Student Center for a gunman after a police officer and another person were shot and killed on the campus in Blacksburg, Virginia, Dec 8, 2011. [Photo/Agencies]