Condoling the loss of lives, Kumar ordered the district magistrate and superintendent of police to inquire under what circumstances people were being carried in a truck meant for freight, an official statement said here.
He also instructed the state police chief Abhayanand to ensure that no person is ferried in a freight vehicle, which should be used exclusively for carrying goods.
Those who violate the direction should be taken to task, Kumar said.
Around 35 labourers were returning to Lesiganj village in Daltonganj from Aurangabad after harvesting crops when the truck overturned on NH 139 before rolling into a roadside ditch in the early hours today. The 25 killed included 11 children and eight women.
The truck driver, who was drunk, fled the spot along with his assistant.