(CNN) -- More than half of the students implicated in last year's cheating scandal at Harvard University have been required to withdraw from school for a period of time, a dean said in a statement Friday.
More than 100 students were investigated for plagiarism or for having "inappropriately collaborated" on a course's take-home, open-book spring final exam, said Michael D. Smith, Harvard's dean of the Faculty of Arts and Sciences.
Many of those who were not forced to withdraw face disciplinary probation at the Ivy League institution in Cambridge, Massachusetts, and the remaining were cleared.
The school would not release the specific breakdown of the numbers of affected students.
The Harvard Crimson, the school's flagship student-run newspaper, identifies the class in which the cheating allegedly occurred as Government 1310: Introduction to Congress.
An attorney representing two students involved in the case said some students discussed questions on the exam and worked together to come up with answers.
Other students e-mailed their exam answers to peers in the class, who in turn used those answers on their exams, said attorney Robert L. Peabody.
He said Harvard tried to put together a disciplinary process that was fair, but that the school was too slow in its response.
"The process was mind-bendingly slow, delayed and postponed over the entire course of the semester, which added to students' stress and anxiety about how this was going to shake out," Peabody said.
In a statement released when the cheating scandal first became public in August, Harvard University President Drew Faust said, "These allegations, if proven, represent totally unacceptable behavior that betrays the trust upon which intellectual inquiry at Harvard depends."
During grading, "the faculty member teaching the course questioned the similarities between a number of exams," according to a statement from Smith during the initial investigation.
The board then reviewed the tests and interviewed the students who submitted them. It eventually launched a wider probe into the allegations.
CNN's Poppy Harlow contributed to this report.