CPI(M) General Secretary Sitaram Yechury said the voices of those protesting against the contentious citizenship law, National Register of Citizens (NRC) and National Population Register (NPR) cannot be muzzled, as he hailed the protests in West Bengal during Prime Minister Narendra Modi's visit.
Activists, who hit the streets on Saturday with placards that read "Modi Go Back" and "Down with BJP", continued their sit-in all night at Esplanade, insisting that their agitation would continue until the prime minister leaves the city.
"The voices of those resisting the discriminatory CAA-NRC-NPR cannot be muzzled," Mr Yechury tweeted.
"The PM is out of touch and thinks he can brazen it out. He cannot. India's young have arrived and will take this country forward," the CPI(M) leader said.
PM Modi met Chief Minister Mamata Banerjee on Saturday after arriving in Kolkata on a two-day visit to the state.
The meeting at the Raj Bhavan came amid a bitter face-off between the BJP and the Trinamool Congress over the amended Citizenship Act that has triggered massive protests across India.