Chief Minister Mamata Banerjee appealed to the people to use democratic means of protest and warned that action would be taken against those taking law into their own hands, while the opposition BJP threatened to move the Centre demanding President's Rule if the "violence" perpetrated by "Bangladeshi Muslim infiltrators" went on unchecked.

The maximum violence was reported from Murshidabad and Howrah districts, while a number of other districts also bore the brunt of the protesters fury as the sky was covered with black fumes from burning vehicles and tyres with rampaging mobs armed with rods and sticks laying siege on stations and highways.

A large number of mail, express and passenger trains were cancelled by the South Eastern Railway and Eastern Railway -- two important zones of the Indian Railways -- which run the services to most parts of the eastern state. At many of the stations, panicky railway employees fled from their posts fearing for their lives.

At Krishnapur station in Murshidabad, a number of trains were attacked, and several coaches were burnt by the protesters, who also torched the Lalgola station in the same district and Harishchandrapur in neighbouring Malda.

Railway equipment kept at Eastern Railway's Beldanga station was burnt by the protesters, who also damaged a fire brigade engine and set it afire. When police rushed in, they were stoned.

On Friday, protesters carrying posters against the Citizenship Amendment Act and the proposed National Register of Citizens had vandalised the railway station, torched the station master's cabin and ransacked the ticket counter before setting it ablaze.

In Suti in the same district, three state buses were vandalised on Saturday morning and one of them was torched by the protesters after they forced out the passengers. A toll plaza was also charred.

In Raghunathganj, National Highway 34 was blocked for three hours at Talai More as protesters burnt tyres on the road.

A large group of protesters shouting slogans against CAA and NRC vandalised the Basudevpur halt station and indulged in arson.

Mobs also squatted on the railway tracks at Poradanga, Jangipur and Farakka stations in Murshidabad district and Bauria and Nalpur stations in Howrah district.

Train movement between Lalgola and Palashi stations was completely jeopardised, railway sources said.

Six buses were torched near Garfa Mor on Kona Expressway in Howrah district, before the police lathi charged to remove the blockade. The highway was also obstructed at Domjur.

In Sankrail station under South Eastern Railway, the ticket counter was set ablaze and the panel room was ransacked by angry protestors.

Railway sources said the protesters also uprooted the rubberised surface of the level crossing and used hammer and rod to damage the tea stall on the platform, besides throwing the concrete benches on the line.

The mob then spread out to the nearby Champatala crossing and halted vehicular movement by putting up road blocks with burning tyres.

At Chengail station, protesters damaged the booking office as also an empty rake, and set fire to the level crossing, railway sources said.

Trains stopped plying on the South Eastern Railway's Howrah-Kharagpur section following the disturbances.

The Eastern Railway cancelled a dozen express and mail trains on Saturday, and nine more which were scheduled to chug out on Sunday. Five long distance passenger trains were cancelled on Saturday, besides four which were to move out on Sunday.

The South Eastern Railway also cancelled over a dozen express and mail trains due to start on Saturday, and another train scheduled for Sunday. Some long distance passenger trains also suffered the same fate.

Suburban train services of Eastern Railway on the Sealdah-Hasnabad section were also disrupted after a blockade at the Kankra Mirzanagar station.

Chief Minister Mamata Banerjee, who has promised that CAA won't be allowed to be enforced in the state, said in an appeal: "Agitate by using democratic means, but don't take the law in your hands, don't indulge in road or train blockade."

"We won't tolerate if common people are made to suffer. Those who are creating disturbances, hitting the streets to take the law in their own hands, won't be spared. We will take steps as per the law against those torching buses, stoning trains and destroying government property," she warned.

State BJP chief Dilip Ghosh accused the state government of not taking action against those indulging in arson and destruction of public property for the sake of "vote bank" politics.

Ghosh said a 'particular community', which is an integral part of her (Banerjee's) politics, was indulging in violence.

"Where are the police, where is the administration," he asked.

State Education and Parliamentary Affairs Minister Partha Chatterjee said the administration was on alert but claimed that "it is not always possible to control people's resentment."

In an apparent appeal to the minorities, senior state minister Firhad Hakim urged them not to strengthen the BJP in the state by fomenting 'lawlessness'.

Hakim, a prominent Muslim face of the Mamata Banerjee-led government and the ruling Trinamool Congress, said the fight against NRC and CAA is not a "fight between Hindus and Muslims".

"If a community creates lawlessness, the majority will get annoyed. That in turn will only benefit the BJP," said Hakim.