He said: "Protestors have smashed a number of commuter buses and set up road blocks in different parts of the state."
Kanojia said many protestors had been taken into custody and thousands of security personnel deployed.
Soumitra Majumdar, a spokesman for Eastern Railways, said train services had been severely disrupted with long-distance trains halted, as protestors squatted on railway tracks.
|"They called themselves communists but they fire bullets at poor farmers"|
Gopi Mondal, 65, taxi driver
Many strikers blame Wednesday's killings at Nandigram, 150 km southwest of Kolkata, on the state government, which wants to set up a chemical industrial hub on farming land despite opposition from villagers.
Police fired on the villagers in clashes trying to enter the earmarked farming land.
Gopi Mondal, a 65-year-old taxi driver, said: "They called themselves communists but they fire bullets at poor farmers."
The killings have become a national controversy and put the spotlight on India's policy of setting up low tax Special Economic Zones (SEZs) by acquiring land from farmers.
At least eight strikes have been called in West Bengal in the past six months against the state government's economic reforms, including its SEZ policy.
In recent years, the state's communist rulers, who initiated India's most successful land reforms in the 1970s and 1980s benefitting millions of peasants, have switched from their pro-rural stand and pushed for industrialisation of the state.
On Friday, protesters put banana leaves on overhead wires of electric trains, stopping their operations while others blocked state highways, police said.
In Kolkata, two buses were set on fire. In Siliguri, in the north of the state, protesters set fire to railway tracks at a station.
The Trinamul congress, the state's main opposition group, called the day-long strike.
Mukul Roy, general-secretary of the Trinamul congress, said: "The government will now find out that it can no longer play with the lives of innocent villagers."
The state's industrial hubs of Durgapur in the west and in Haldia, off the Bay of Bengal, were affected by the strike.
At least 21 people have died in Nandigram in violence against the proposed chemical hub since January.
The killings has resulted in the federal government putting on hold many proposals across the country for SEZs, touted as important for boosting India's industrial growth and closing the manufacturing gap with China.
|Protesters in Nandigram on Thursday set|
fire to a local government building [EPA]
On Thursday, about 2,000 farmers gathered outside a hospital where those injured on Wednesday were being treated.
They chanted angry slogans, marched towards a local government office and set fire to the building, witnesses said.
Police responded with baton-charges and tear gas on Thursday, dispersing protesters who quickly regrouped elsewhere.