Six people, including a family of three from Dombivli, were killed after the driver of a speeding tar-laden truck crashed into eight vehicles on a busy bridge on the Katraj-Dehu Road bypass on Thursday morning.
Ten others were injured in the accident.
The accident spot, on the outskirts of Pune at Wadgaon, is a major entry point to Pune for vehicles coming from Mumbai and Bangalore on the NH4.
The three of a family, Ravindra Tukaram Sawant, Sarika Ravindra Sawant and Rewati Ravindra Sawant, were returning to their home in Mumbai from their village in Satara.
The police said they are trying to trace the truck driver, who fled the scene and has been missing since.
Eyewitnesses and other motorists said the truck driver was speeding and had overtaken several vehicles before he reached the bridge.
The truck, which was going towards Mumbai, first crashed into a tourist bus in front of it.
The driver seemed to have lost control, as he went on to hit two cars, a jeep and a few motorbikes.
The driver then crashed the truck into the sides of the bridge and it turned turtle. However, trees lining the bridge stopped it from falling on to the service road below.
The police suspect the driver might have lost control because of some technical fault with the vehicle.
The Wadgaon flyover is a major bottleneck on the route as it connects both sides of NH4 and major parts of Pune city.
The accident held up traffic on the stretch for a few hours.
As investigation into the accident continues, rescue workers cleared the truck from the road in a few hours.
The others victims are Subhash Vinayak Chowdhari, Balaji RamSing Rathod and Marebar Gaikwad, all of whom were killed instantly.
The Sawant family stays in Dombivli and were on their way back home after spending a few days with relatives at their native village.
The 10 other people injured in the accident were taken to a private hospital.