University College London has told student activists they must carry out "community service" or face more severe punishment after their involvement in an occupation to support striking lecturers.
A small group of UCL students occupied the university's registry and key offices such as the council room over four days in late March.
The students said they occupied the rooms to show their support for the University and College Union's national strikes over pensions, pay and jobs, and in protest against UCL's decision to raise fees to £9,000 - the maximum allowed - in 2012.
In a bid to end the occupation, UCL threatened High Court action against 13 people: 11 students, one students' union officer and a UCU branch executive officer who reportedly visited the occupation. The occupiers withdrew before legal action was carried out.
UCL then told the 13 that they would be subject to disciplinary action - a move the students describe as "political victimisation".
The university denied this charge. A spokesman said UCL had told "representatives of the occupation we would offer them the opportunity to undertake community service rather than being pursued for costs. The nature of that community service is still under discussion."
The spokesman said no damage had been caused by the occupiers, but the university had incurred legal costs.
He added that if the community service were not accepted, "then more serious disciplinary action would follow, and this would probably involve financial penalties".
The affair highlights the challenge universities face in responding to recent student activism, which has been resurgent on campuses following the government's cuts to higher education funding and the trebling of fees. Three student occupations have been carried out at UCL in recent months.
Michael Chessum, students' union education and campaigns officer at the university, and one of the group he called the "UCL 13", said the university was "going for a punitive line to try to stop occupations happening in the future". It has "decided to embark on a campaign of political victimisation against those in the occupation", he added.
Mr Chessum argued that the university had targeted "known activists" involved in previous fees protests - even though some of them visited the March occupation for "as little as half an hour or 45 minutes".
Sean Wallis, UCU branch secretary, said the students notified of disciplinary action "seem to have been drawn up from a hit list rather than people (about whom) there was particular evidence of malfeasance in relation to this occupation".
The university's spokesman said the "particularly disruptive occupation" left students "unable to collect bursary and hardship cheques, access disability services, or deal with exam timetable queries".
He added that "all of those individuals we are in touch with were in the occupation after they were told to leave. Legal and other costs will run into thousands of pounds."