A professor has filed suit accusing Ohio University of defamation, saying school officials wrongly accused him of allowing mechanical engineering students to plagiarize.

The lawsuit by Jay Gunasekera, filed Wednesday, also claims that university officials characterized the former department head as unethical, dishonest and supportive of academic fraud. It seeks more than $25,000 in damages.

Thirty-seven engineering graduates were accused of plagiarizing parts of their master's degree research projects, and a school committee reported that there was rampant and flagrant plagiarism in the program for more than 20 years.

The report did not name professors accused of supporting plagiarism, but in May the committee said Gunasekera and another professor should be fired.

Gunasekera's lawyer, John Marshall, said the university issued the report without evidence that the professor knew about the plagiarism.

University officials said they would vigorously defend the school from the lawsuit.

Gunasekera was chairman of the department for 15 years before he stepped down in June, and in 2003 he was named a distinguished professor. He remains a professor but has been stripped of his role as a graduate student adviser.