A student at the Banaras Hindu University (BHU) was reportedly slapped on Monday by an unidentified man for shouting slogans at the convocation where Prime Minister Narendra Modi was the chief guest.

The incident happened when the student, identified as Ashutosh Singh, was being taken away by the Varanasi Police.

"The students union has been prohibited since 1997. The students here are suppressed and not allowed to raise their voice," he said while being taken out of the function by the police, according to ANI.

Singh shouted slogans when Modi was getting down the stage after addressing students, teachers and others gathered to attend the 100th convocation of the central university in Varanasi, IBN Live reports.

The student reportedly demanded the resumption of student's union elections in the university. India Today quoted Singh as shouting: "Modiji hum chhatron ki awaz suniye (Modiji please listen to the students)."

Singh was reportedly detained, but will be released soon. The person who thrashed him is reported to be a BJP worker.

The police had earlier prevented the Bahujan Mukti Morcha (BMM) members from entering the convocation venue. The BMM members had reportedly come to speak to Modi over Rohith Vemula's suicide. Vemula, a PhD student at the University of Hyderabad, committed suicide in the hostel room on Jan 17, 2016.

Students union elections on the campus took place for the last time in 1996. BHU banned the union for an indefinite time when a major clash broke out in 1997 during elections, resulting in the death of two students, Hindustan Times reports. 

However, BHU agreed in 2007 to form a student body â€” Student's Council — for which the members were elected by the university administration. They allowed elections for the council in 2011 for the session 2012-2013.

Since then, the BHU administration appoints a professor as students' council president and the vice-president appoints the dean of students. The general secretary of the students' body is appointed by the representatives of undergraduate, post graduate and PhD classes. These representatives are appointed by the students.