Tens of millions of workers in India are on a daylong strike demanding higher wages and to protest against the economic reforms of the government.
While public transport is also interrupted in areas of the state, banks, government offices and factories are shut.
The government says the reforms are needed to reinforce the economy.
But trade unions say the government hasn’t addressed the demands of the workers in banking, telecommunication and production industries.
Tapan Sen, general secretary of the Centre of Indian Trade Unions, told the BBC that more than 150 million workers in different industries were on strike.
But there is no independent corroboration of the amounts given by the unions.
Banks, shops and schools shut down in areas of the state, including in the southern Karnataka and Kerala states, where public transport was also interrupted, according to reports.
News channels showed flag waving protesters.
More than 20 protesters were detained after two government buses were damaged by them in West Bengal, senior police official Anuj Sharma told AFP.
Ten major unions called the strike after talks with Finance Minister Arun Jaitley broke down, with leaders reports said.
“This strike is against the central government, this strike is for the cause of the working people,” Ramen Pandey of the Indian National Trade Union Congress told the AFP news agency.
“Our strike will be 100% successful… we will prove this strike is the world’s biggest ever.”
Since taking charge PM Narendra Modi’s BJP government has began economic reforms and is trying to comfort labour laws to attract foreign investment and make it simpler to work in the state.
The government also plans to sell its stake in state- owned companies, which are incurring heavy loses.