According to the report, the incident took place when the labourers were being ferried for the work on the Nagpur-Mumbai Samruddhi Expressway project at around 12 noon.
A total of 16 labourers were travelling in the vehicle that was also carrying steel materials for the project.
Buldhana Superintendent of Police Arvind Chavria said the vehicle was speeding and it overturned due to a large pothole on the road.
Police personnel rushed to the spot upon receiving the information and commenced rescue operation.
Four injured labourers were taken to a nearby state-run hospital.
Most of the labourers hailed from Bihar and Uttar Pradesh.