Subscribers to a University text message alert system grew 10 percent last week in the wake of the Virginia Tech shooting, a University official said.

The Office of Public Safety and Emergency Management and the University Police Department sent a campus-wide e-mail Tuesday night informing students and faculty to sign up for Alert DC, the text-message based alert system, to check Campus Advisories and gave instructions on how to be safe in the event of an “active shooter” on campus.

In the case of an “active shooter,” the e-mail advised students to leave buildings where a shooter might be, call UPD to describe the situation and to take shelter in another building. Those not immediately in presence of an attack should take “shelter-in-place.”

John Petrie, assistant vice president for Public Safety and Emergency Management, said that his office released the information this week because it now knows more details about the Tech shootings.

Petrie said that the e-mail was sent because he wants to give students the tools necessary to handle an emergency.

“(We want) to empower people with information that isn’t coming into them in a way that frightens them about the situation that they’re in,” Petrie said, “but informs them and empowers them.”

Officials forwarded the e-mail to the Alumni Office and the Office of Parent Services listservs. The parent e-mail list includes 6,500 addresses. University Police Chief Dolores Stafford said that the e-mail was partly a response to questions she received from students.

“We received calls and e-mails about the Virginia Tech tragedy,” Stafford wrote in an e-mail, “so I gathered information I could forward to the community to answer some of the questions that were being asked of me and other staff in my department.”