The incident took place at around 5 PM on the Kanpur-Allahabad road when the bus was on its way to Fatehpur from here, they said.
"The bus collided head-on with the truck after the driver lost control over the vehicle due to some mechanical failure and went on the wrong side of the road," SP (Traffic) Sarvanand Yadav said.
The eight seriously injured people, including the truck's driver, have been admitted to the medical college, the ASP said, adding the condition of some is said to be critical.
Bodies of four men and a woman have been retrieved from the wreckage and have been sent for postmortem, the officer said.
The road was blocked for several hours due to the accident, he said.
(More details awaited)
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