The emails were sent using Guerrilla Mail, a free online application that generates temporary anonymous email addresses. Additionally, Kim used a free application called TOR, which generates a random anonymous IP address for temporary use that is difficult for law enforcement to trace. According to the affidavit, authorities were able to determine that Kim had accessed TOR on the Harvard network before sending the email.

Harvard Sophomore Charged in Bomb Threat | News | The Harvard Crimson Tuesday, December 17, 2013 @ 10:49pm