The accident, which also left five injured, took place in Incahauli town, when the truck ploughed into the Tavera car.
"While five people died on the spot, three succumbed while being treated at a hospital," Superintendent of Police (Rural) H.N. Singh told reporters in Meerut, some 500 km from Lucknow.
"Of the five injured being treated at the district hospital, the condition of three is stated to be critical," he added.
According to police, the Meerut-based family was returning from a marriage function when the accident occurred.Police are yet to nab the driver of the truck, who managed to escape after the accident.
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