A university has written to all its students threatening them with disciplinary action for comments made about staff on the internet.
The university has threatened students with legal action
Keele University said the remarks on Myspace and Facebook were unacceptable, and students may face legal action from the members of staff concerned.
A spokesman said the university would establish new rules for using those websites on campus.
Students should use "legitimate ways" to express dissatisfaction, they added.
In a statement the university said: "Students may face legal action from the members of staff concerned for defamation and harassment.
"A number of students have already been written to by the university warning them of the unacceptable nature of their comments on Facebook and that any further activity of a similar nature will be dealt with severely.
"Please note that there are legitimate ways to express dissatisfaction with the student experience without resorting to such communications."