Bomb squads are searching the University of Iowa’s College of Dentistry after an e-mail bomb threat. The school is closed today and will reopen tomorrow under much tighter security. U-of-I spokeswoman Ann Rhodes says this latest threat differed from other recent threats and was signed from “me jones.” She says it was directed to individuals in the College of Dentistry that were not minorities.Several recent threats have targeted minorities on the U-of-I campus and Rhodes says this latest message had to be viewed as a legitimate danger. She says it’s always difficult to assess the threat, but she say in light of recents threats, the University decided to take action.When classes at the dental school resume tomorrow, all exterior doors will be locked and anyone entering the building will be subject to search. Today is the five-year anniversary of the Oklahoma City bombing which killed 168.