Officials are investigating an e-mailed death threat that was sent to Harvard students on Friday afternoon.
In an advisory to the campus community, Harvard University police said that "hundreds of Harvard students and affiliates received an emailed death threat" at about 4:45 p.m. on Friday.
"The author threatened to come to campus 'tomorrow' to shoot the email recipients," the advisory said. " Harvard University Police Department (HUPD) immediately began investigating, and also notified other local law enforcement agencies as well as the FBI."
The advisory continued, "While we cannot verify at this time that this is a real threat, every member of our community should be familiar with these Active Shooter Safety Guidelines, which were developed based on guidance from the U.S. Department of Homeland Security.
HUPD will increase its presence across campus this weekend."
Campus police urged students to call the department at 617-495-1212 if they see anything suspicious or have "pertinent information to share."