Authorities in Blacksburg, Virginia say a police officer and another person have been shot and killed on the campus of Virginia Tech University, where a single gunman killed 32 people in 2007 before committing suicide.

A campus-wide alert issued Thursday urged people to stay indoors and advised visitors to stay away from the school.

The school said on its website that the officer was shot on campus during a routine traffic stop, adding there were witnesses to the shooting. The school says the shooter ran toward a parking lot on campus where a second person was found dead.

A search is continuing for a suspect.

Earlier this year, federal officials fined the school, formally known as Virginia Polytechnic Institute and State University, for waiting too long to notify staff and students during the 2007 rampage, which was the deadliest mass shooting in modern U.S. history.