Labourers on their way to work at an ancillary unit of the Tata Motors' [Get Quote] Nano project at Singur and a trolley van-puller carrying them were allegedly assaulted on Wednesday by Trinamool Congress workers who were laying a seize to the small car plant.

Four or five labourers were proceeding to their work place when they were stopped and beaten by activists of Trinamool Congress, police said.

One of the victims lodged a police complaint, saying the attackers threatened them not to work for the project.

The trolley van-puller was also instructed not to ferry any worker to the project site. Fearing attack, all trolley van-pullers stayed away.

The assaulted labourer, who lodged a complaint said, he and some other labourers, all from Bihar, had been staying in a rented house in Singur, but after today's incident they were feeling insecure and would shift somewhere else.

However, he said, he would continue to work with the project.

Sub-divisional Police Officer Chandernagar said the incident would be investigated.