The labour unrest followed the suspension of a worker by the company. Union leaders accused Maruti of taking action against workers "without any reason". The company said the union prevented officials from taking action against the worker who beat up a supervisor on the shop floor.
The fire started around 6.15 p.m. in the human resource department and spread to the paint shop where it was put out around 9 p.m., said an official.
Fire officer I.S. Kyashap told IANS: "A large part of the company plant was completely destroyed in the fire."
A large number of vehicles that were parked in the company premises were either set on fire or vandalized, an official said.
Police used force in which several workers were injured, a union leader said.
A company statement said that workers at the Manesar plant turned violent, attacking and injuring executives and managers. At least 40 managers and executives were injured.
The attackers also set fire to property and damaged facilities, said the statement.
More than 20 fire tenders, including those of the army, DLF and other companies, were rushed to douse the blaze.
Whether the fire was ignited by agitating workers or it started accidentally during a clash could not be confirmed.
According to sources, the workers were agitated that instead of considering a demand notice regarding their increments, the management started targeting their leaders.
The company said after the protesting workers locked the plant gates in the evening, the officials tried to talk to them to resolve the issue.
During the talks, the workers attacked the senior managers and executives. They damaged office furniture, broke the glass panes and ransacked the office property, the company statement said.
Work at the Manesar plant had to be stopped following the voilence. The Gurgaon plant operated normally, the statement said.
The company's latest plant at Manesar has been specially designed for manufacturing diesel cars. The plant churns out Maruti Suzuki's best selling compact car Swift, A-Star and sedans like DZiRE and SX4.