University of Iowa public safety officials say they have some clues to the origin of threatening e-mail sent to students and administrators in the College of Dentistry. The e-mails, and a letter sent to a dentistry student, were targeted at minorities. Public Safety Director Charles Green says the clues have not yielded a suspect. Green says the person is covering their tracks very well and they haven’t been able to find the author of the e-mails. He says they haven’t given up on finding the person who sent the e-mails. He says the e-mails aren’t untraceable, only that they’ve not been successful at it yet.Green won’t say if they may have found the computer where the e-mails were sent as they don’t want to release too much information which would jeopardize their investigation. A lab coat was recently set on fire in the Dentistry School. Green they are looking into a connection to see if one person may be responsible for all three acts.Green would not characterize this as a tough case to crack. He says any investigation takes time.He says he remains confident about the case.One detective is working full time on the case and he’s being helped by other officers as well as the Iowa City and Coralville police departments. The U-of-I Office of Affirmative Action plans to hold a “Day of Dialogue” from noon until two p-m Friday at the Iowa Memorial Union to talk about the situation.

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