The 186-year-old Scottish Church College was shut down till further notice on Wednesday night "on account of the continuing students' unrest".

The teacher-in-charge, Arpita Mukherjee, put up the notice at the college gate after students supporting the Trinamul Congress Chhatra Parishad laid siege to her office and the assembly hall from 3pm to 9pm.

What the Trinamul student leaders managed to do has not happened in one of the oldest missionary colleges in the city for at least the past 30 years.

Higher education minister Partha Chatterjee had grandstanded a few weeks ago about how his party would not tolerate indiscipline in colleges but the conduct of the party's supporters at Scottish Church makes it clear that the message has not percolated down.

The government did not allow student elections in colleges last year. So, technically, no college has a formally elected union. But the outgoing unions still hold fort and consider it their right to harass teachers.

According to Mukherjee, the students started their agitation protesting against the presence of the former principal and current rector, John Abraham, in a meeting to discuss how a new building on the campus would shape up.

"The students were banging on the door of my office while we started the meeting, which was also attended by the rector. John Abraham had been invited because the building was conceived during his tenure. He had also helped us to gather funds for its construction. The students kept demanding that Abraham leave," said Mukherjee.

A teacher who attended the meeting said the students also alleged that John Abraham was responsible for the resignation of his successor Amit Abraham late last month.

Mukherjee alleged that when she resisted the students' demand, they started abusing her. "I tried to explain that we cannot ask the former principal, who is also the rector of the college, to leave. But they did not listen to me and began verbally abusing me and other teachers. We were forced to close the college," said Mukherjee.

Souryadeep Mukherjee, a student leader at Scottish Church, justified the agitation saying "there was no alternative". He admitted that the protest was staged because Abraham had taken "several unpopular decisions" during his tenure as principal.

Mukherjee, who was a class representative in the last elected union, claimed: "The students' union, which is no longer in office, was not involved in today's agitation. General students led the protest."

John Abraham refused comment when contacted.

A notice announcing that the college is being shut was put up on the notice board after the former principal left the college around 9.30pm.

Mukherhee said the decision was taken after consulting Bishop Reverend Ashoke Biswas, the chairman of the college council. The Calcutta diocese of the Church of North India runs the institution.

Mukherjee had taken over as the teacher-in-charge after the church had accepted Amit Abraham's resignation. Sources in the church had said they were not happy with his conduct.#A teacher said the students union had been at loggerheads with John Abraham over several issues. "In July 2015, when he wanted to raise the fees, students had confined him for hours without realising that as a missionary institution, the college was authorised to set its own fee structure. They also protested a dress code that he had set without realising that the college was entitled to have its own dress code."

He explained that the students' perception that John Abraham was instrumental behind Amit Abraham's resignation had only worsened the situation.

Last month, SA Jaipuria College had to be shut down following factional feud between two groups of Trinamul supporters. The party unit in the college was disbanded after that round of agitation.