Police fired tear gas and charged crowds of angry farmers with bamboo batons on Monday, dispersing thousands of protesters demanding more compensation for land seized by the government for a new car factory.

The farmers say the government payments are below market rates.

They defied a state government ban on gatherings of four or more people at the construction site in Singur, a village about 20 miles northwest of Calcutta, the capital of West Bengal state.

Protesters set fire to a police truck, and two police officers and a number of protesters received slight injuries during the clash, police superintendent Supartim Sarkar said. Four protesters were arrested, he said.

"We can't have this unrest. There is a factory being built and we must have security," said B. Baidya, another superintendent of police.

West Bengal's communist government sold fertile agricultural land last year to Tata Motors Ltd., a division of the Tata Group, to build a car factory. The plan has sparked repeated protests from farmers and opposition politicians.

Alok Chakrabarty, a tenant farmer, said the state government was taking land from farmers and giving it to industrialists.

"We will have nothing left. We must stop them," said Chakrabarty, 28, who received 25,000 rupees (US$540; €415) in compensation from the government.

"This will not last me for my whole lifetime," Chakrabarty said.

Monday's protest was organized by the opposition Trinamool Congress party.

Last month, the Tata Group held a brief prayer ceremony marking the start of construction. More than 500 policemen prevented protesters from disrupting the ceremony.

The company said it has begun training local people for future employment at the 10 billion-rupee (US$226 million) plant.

Tata Group is one of India's leading business conglomerates, with interests spanning steel, software services, hotels, chemicals and insurance. Its vehicle division, Tata Motors Ltd., makes cars, buses and trucks and is listed on the New York Stock Exchange.