It's believed that the gunman who opened fire at the Virginia Tech campus Thursday and killed a police officer is also dead.

Earlier, officials said that two people had died and that the gunman was still on the loose. However, later in the day reports said that the gunman himself was the second victim.

However, police would not confirm the second victim's identity during an afternoon news conference, only saying they were confident the situation was under control.

A news release issued by Virginia Tech said the police officer had pulled someone over in a routine traffic stop Thursday. During the traffic stop the officer was shot and killed.

The officer has been identified as 39-year-old Deriek W. Crouse.

Crouse, an Army veteran and father of five, had joined the Virginia Tech Police Department on in October 2007.

Later, the university said that a gun had been found near the second body, located in a parking lot. But the identity of the body wasn't immediately known.

Immediately after reports emerged about the shooting, university officials put the school on lockdown and told students and staff to stay inside the school.

The shooting came as Virginia Tech was appealing a US$55,000 fine by the U.S. 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.

Though university officials were heavily criticized for their handling of the 2007 incident, the school used text messages and email to ensure that students were kept updated. Messages also warned students and faculty to stay inside and away from danger.

Updates were sent to students about every 30 minutes, according to school officials.

As heavily armed police circulated through the campus after gunfire erupted, many students preparing for final exams hid in buildings and kept out of sight.

"A lot of people, especially toward the beginning were scared," said Jared Brumfield, a student who was locked inside a student centre around 1:30 p.m. "A lot of people are loosening up now. I guess we're just waiting it out, waiting for it to be over."

With files from The Associated Press