IOWA CITY, Iowa (AP) – Officials say some students used stolen teacher passwords to change some grades at the University of Iowa. The officials said Thursday that about 250 students, faculty members and other staffers have been told their university IDs and login information were taken by unauthorized devices that had been attached to university computers in classrooms and computer labs. The university says only 5 percent of those accounts were later used by someone other than the account holder.

University staffers are checking computers for suspicious devices and developing plans to increase security measures. Officials are encouraging people on the university system to change their passwords. Officials say that if investigation determines a student has cheated, university disciplinary action could include expulsion or suspension.