Their protest - over outsourcing of pay contract while supporting lecturers' pay protests - is backed by a letter signed by more than 100 academics

Students have occupied a University of Sussex campus building for the second time in year in protest at the working conditions of university and what they say is the "privatisation" of university services.

Up to 40 students will go into their fourth day of occupation on Friday - backed by a letter signed by more than 100 academics.

The academics, in a letter to The Independent, complain that the university spent £81,812 in legal fees obtaining an injunction against the students the last time the staged an occupation - money that could be put to better use elsewhere.

The immediate issue the students are protesting about is the handing over of the catering contract to an outside contractor - which, they say, has led to staff being employed on worse conditions.  They are also supporting a national strike by lecturers over a one-per-cent pay offer next week.

The university said on Thursday night it was taking legal action to evict the demonstrators again - which would be heard at Brighton County Court next Tuesday.

John Duffy, the university's registrar, said the occupation was being staged by the "same minority of students who were involved in occupation earlier this year".  "Those undertaking this disruptive activity are a very small number of students out of a community of 15,000 people," he added.

In their letter, the academics say: "We consider their actions - and ours next Tuesday - to be part of a broader struggle. "

They say they consider the legal fees "unnecessary and misplaced" in that the injunction sought to any unauthorised protest on campus - but failed to do so in practice.