The deceased were identified as Badalu, 70, who ran the eatery on the Sisaiya-Bahraich road, his daughter Nazima, 35 and granddaughters Mahek, 3 and Ruby, 18, they said.
The speeding truck overturned on their eatery, killing all four on the spot, police said, adding that the negligence of the truck driver is said to be the cause of the accident.
The truck driver has been taken into custody, police said.
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