Students occupying Trinity College Dublin's 18th century dining hall in a protest over extra charges have been denied access to toilets and water by security at the college, according to the students' union.
It says that at around 5pm this evening security entered the building and cut off students' access.
Trinity Students' Union says around 100 students are also occupying the exam hall. This is in addition to around 50 who are staging a sit-in at the dining hall.
It says they have been told they will be allowed to leave but will not be allowed to re-enter.
The occupation began yesterday and is one of a series of actions taken by students in opposition to a €450 charge that the college has introduced for the 1,700 or so students who need to resit exams every year.
Trinity College Dublin authorities say the charge is part of a package designed to make charges fairer for students.
People Before Profit TD Richard Boyd Barrett characterised the college's action this evening as "shockingly draconian."
He called for TCD management to "show a bit of decency towards their students" who were protesting against unjust and extortionate fees that so many of them could not afford.
This evening, the college’s authorities said students occupying the hall are free to leave at any time they want and that the college is taking all steps to ensure that the students inside are safe.
The college said it was not letting anyone else into the building, as there were concerns that large numbers of non-students had been invited in.
In a statement it said this would result in unacceptable risks for all concerned.
In a tweet tonight the Provost of Trinity College Dr Patrick Prendergast said alternative proposals on supplemental examination fees will be considered at the next Board meeting.
Agreed with @tcdsu & @trinityGSU that we will seriously consider alternative proposals on supplemental exam fees, modular billing & PG/Non-EU fees at the next Board meeting, and that Trinity is a university that belongs to all of us who study and work here #TakeBackTrinity— Patrick Prendergast (@pjprendergast) March 14, 2018