McGill University students staging a sit-in in the James Administration Building prepared to bed down on Tuesday night, after failing to win any concessions from a representative of the university administration.

Some 20 students were camped outside of the sixth floor office of McGill Deputy Provost Morton Mendelson. About the same number were planning to spend the night on the first floor, complaining that security guards had refused them access to the building's washrooms.

"At this point, the building is on lockdown," said protester Jaime MacLean, who had been at the protest since it began at around 11 a.m. Tuesday. "The guards are not letting anyone who leaves re-enter."

Students want the university to ratify a referendum held last fall regarding the place of two student groups on campus – CKUT radio and QPIRG – the Quebec Public Interest Research Group. The university contends the wording of that referendum question was confusing, and it wants a second referendum to be held.

Earlier in the day, media were barred from the university's downtown campus, and university spokesperson Douglas Sweet would not say if the administration planned to evict the student protesters.

At around 6 p.m., representatives met the university's associate vice-principal Jim Nicell, but they said he didn't offer them anything to persuade them to go home.

"It was basically him telling us that we should leave now," said MacLean. "He didn't offer us anything, not even academic amnesty."

Earlier in the day, the students had been threatened with disciplinary action if they refused to end the demonstration, she explained.