The incident took place at a jute plant in Bhadreswar jute mill today morning when the workers started demonstrating in front the plant after finding the suspension of work notice pasted on the mill gate, police said.
They also demanded immediate cancellation of the order and restoration of normal work there, they said.
Several workers entered the manager's bungalow and following an altercation assaulted him, the police officer said.
Mill manager G C Upadhyay was taken to a hospital and later released. Five workers were arrested for assaulting the manager, the police said.
"We had to resort to mild lathicharge to take control of the situation and then arrested five workers of the mill," he said.