The incident took place early today at the Cuttack-Chandballi state highway when the ill-fated van coming from Kendrapara collided with a truck coming from the opposite direction, they said.
Those killed were poor daily wage workers and five of them were women. They hailed from Gandhipalli locality on the outskirts of Cuttack city, police said.
Six persons died on the spot while another died on the way to hospital. The van was carrying about 18 persons, Kendrapara Superintendent of Police Rabi Narayan Behera said. All survivors are critically injured.
They have been rushed to the nearby government-run Nischintakoili Community Health Centre.
Police forces have rushed to the spot to maintain law and order situation, police said.
The cause of the accident is being ascertained, they said, adding that further details are awaited.