"The mishap occurred yesterday on the Pilibhit-Bareilly border killing one Ajay and his son Suresh," an official said.
Ajay's wife Mithilesh (42), who was also travelling in the car with them, sustained injuries in the accident and was admitted to a hospital from where she has been referred to Bareilly, police said.
The truck driver is absconding and efforts are on to nab him as further probe in the case is underway, the official said.