The Arunachal Pradesh-bound private bus to Bandordewa from Dhola in Assam and a truck from Guwahati to Jorhat collided on National Highway 37 at Panisokuwa, the police said.
The injured were admitted to the Jorhat Medical College Hospital where the condition of three persons was said to be critical, the police said.
The road was blocked for some hours following the accident but police later cleared the way by removing the two mangled vehicles.