Trouble erupted around 1.10 pm when the two student factions clashed and later local groups joined the tussle.

The nominations were scheduled till 2 pm.

According to the police, the six students are supporters of Trinamool Congress Chhatra Parishad (TMCP). They received pellet injuries and have been identified as Md Yakubu, Md Imtiaaz, Md Chotu, Md Guddu, Sheikh Kajar Ali and Sharab Khan. They were later admitted to the SSKM Medical College and Hospital.

“The TMCP supporters had first blocked the road in front of the college in protest against the SFI supporters, which led to a clash between the two factions,” said a senior police officer at Lalbazar police headquarters.

The RAF personnel and Combat force were also deployed to bring the situation under control.

Four buses were damaged when groups of students hurled stones.

The TMCP accused local CPM henchman Mukhtar of being the main conspirator behind this violent incident and they demanded immediate action against him.

Leader of the Opposition in the state Assembly Partha Chatterjee said: “To stop the growing influence of the Trinamool in colleges across the state, CPM cadres are resorting to violence.”

“Today at Hari Mohan Ghosh College, a local CPM henchman Mukhtar, who was armed, mercilessly attacked our supporters,” he said.

Chatterjee visited the injured at SSKM Hospital.

The SFI leaders claimed that TMCP supporters tried to enter the college after the scheduled time and violence erupted.

Kolkata district SFI general secretary, Dhrubajyoti Chhatopadhyay, denied any involvement of the SFI in the violence.

“The time for filing the nomination papers was till 2 pm. The TMCP was, however, not aware of it. After the scheduled time they were stopped. Hundreds of TMC supporters stormed into the college with Trinamool Congress flags and started pelting stones,” said the SFI leader.