Tech lockdown

UPDATE 3:40 p.m. - Virginia Tech has lifted the campuswide alert after three teenagers reported sighting a person carrying what may have been a gun. Police have discovered no new information, and university officials say law enforcement will continue to maintain a large presence on the campus.

The university is resuming normal activities, according to the Virginia Tech website.

"Based on the information provided and lacking further information, we couldn't rule out that this wasn't credible," Tech Police Chief Wendell Flinchum said at a press conference this afternoon. "Therefore, we felt like there was no other option than to issue a campus alert and ask our people to remain secured indoors."

"While the alert has been lifted, as always, we suggest that people remain vigilant and report suspicious campus activity," the university's statement said.

UPDATE 1:00 p.m. - Virginia Tech Police in conjunction with four other police departments continue to search the campus for the person who reportedly had a weapon. There have been no other sightings, but classes have been cancelled for the remainer of the day and university officials are asking students not to come to campus.

Police have released a composite sketch based on descriptions of the purported gunman.

The three youths who reported the gunman were 13 and 14 years old, the Richmond Times-Dispatch reports. No shots have been fired and no injuries have been reported.

Larry Hinkler, a Virginia Tech vice president, told reporters the alert was issued because he wanted to "speak first and investigate later."

12:00 p.m.

Virginia Tech is under lockdown today after three children attending a summer camp said they saw a man holding what looked like a gun, an unsettling report on the campus where a 2007 massacre left 33 people dead.

"We have not found the person matching the description," Virginia Tech Police Chief Wendell Flinchum said at an 11 a.m. press conference, the Richmond Times-Dispatch reported. "I'm not sure how many people have been stopped."

He warned people to continue to stay inside and lock their doors. A few thousand students are on campus.

The university issued an alert on its website at 9:37 a.m. Thursday telling students and employees to stay inside and lock their doors. University spokesman Larry Hincker said during a news conference later in the morning that the campus alert remained in effect and that people should stay indoors until further notice.

The children said they saw the man walking fast toward the volleyball courts, carrying what might have been a handgun covered by some type of cloth. Police swarmed the area but said they could not find a gunman matching their description. The university said on its website that no one else has reported a person with a gun or anything suspicious.

Va. Tech Police Chief Wendell Flinchum said that the three children were interviewed, and that the information they gave was deemed credible.

An alert on the school's website said the gunman was reported near Dietrick Hall, a three-story dining facility steps away from the dorm where the first shootings took place in the 2007 rampage.

"We're in a new era. Obviously this campus experienced something pretty terrible four years ago ... regardless of what your intuition and your experience as a public safety officers tells you, you are really forced to issue an alert, and that's where we believe we are right now," said Hincker, the Virginia Tech spokesman.

Federal authorities fined the school in March after ruling that administrators violated campus safety law by waiting too long to notify staff and students about a potential threat after two students were shot to death April 16, 2007, in West Ambler Johnston Hall, a dorm near the dining facility.

An email alert went out more than two hours later that day, about the time student Seung-Hui Cho was chaining shut the doors to a classroom building where he killed 30 more students and faculty and himself. It was the deadliest mass shooting in modern U.S. history.

The school's alert system also was activated in 2008, when an exploded cartridge from a nail gun produced sounds similar to gunfire near a campus dormitory. It was the first time the system was activated after the 2007 massacre. After the shootings, Virginia Tech started using text messages and other methods besides emails to warn students of danger.

On Thursday, officials said they were looking for a 6-foot-tall white man with light brown hair. Officials said the person was wearing a blue and white striped shirt, gray shorts and brown sandals. He was described as clean shaven, according to the university's website.

Police from Virginia Tech, Blacksburg and Christiansburg searched for the man along with Virginia State Police and Montgomery County sheriff's deputies. FBI spokeswoman Dee Rybiski said agents also were on their way to assist.

Gov. Bob McDonnell, who was attending meetings of the Republican Governors Association in Wisconsin, was in contact with law enforcement to ensure all state resources were available to police, said spokeswoman Taylor Thornley.

"Of course, this report is a frightening reminder of the events that took place four years ago on the Tech campus," Thornley said. "Virginia Tech has correctly taken all precautions to ensure the safety of students, faculty, staff and the Blacksburg community while law enforcement, Virginia Tech officials and the administration work diligently to ensure that this incident is investigated thoroughly."

The Associated Press contributed to this report.

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