The incident took place at Bargudar Pul area under Sikrara police station at around 1.30 pm on the Jaunpur-Rae Bareli national highway, District Magistrate of Jaunpur Sarvagyaram Mishra told PTI.
"The UPSRTC bus was going to Jaunpur from Allahabad. At around 1.30 pm, the driver lost control over the vehicle which hurtled down the bridge and fell on the bank of the river," he said.
Two of the seriously injured passengers have been referred to Varanasi for treatment, he said, adding that other wounded persons were undergoing treatment at a local hospital.
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