The incident occurred whe the couple were going to pluck vegetables from their agricultural field in the morning. Both died on the spot, police officials said.
The deceased were identified as Rama Mahto (50) and Manorma Devi (45).
The driver lost control of the vehicle after the accident and it fell into a roadside ditch. The driver, however, managed to escape from the spot.
Angry locals blocked the NH and demanded compensation for the victims' family. They lifted the blockade after officials placated them.