Clashes broke out between BJP supporters and student activists and those of the Left and Trinamool Congress Chatra Parishad (TMCP) during Amit Shah's roadshow in the city on Tuesday, officials said.
Trouble began after stones were pelted at Amit Shah's convoy as it passed through College Street and the arterial Bidhan Sarani on its way to Swami Vivekananda's residence in north Kolkata, a little over 3.5 km from Esplanade in the heart of the city, where it began.
A scuffle broke outside the Calcutta University campus on College Street, when student activists of both the Left and the TMCP shouted slogans against Shah, they said.
They showed black flags and waved posters with "Amit Shah go back" written on them.
The police controlled the scuffle.
A clash took place outside Vidyasagar college and university hostel when TMCP activists threw stones at Shah's convoy, the officials said.
The agitated BJP supporters locked the gates of the hostel and set cycles and motorbikes parked outside on fire.
They also threw stones at the building.
A bust of Ishwar Chandra Vidysagar, after whom the college is named, which was outside hostel building was broken by BJP supporters during the clash, the officials said.
A huge police contingent was rushed to the spot and controlled the situation, they added.