Nine people were burnt alive and six critically injured when a state transport bus caught fire in Amethi on Tuesday, police said.
Besides, fourteen others also sustained burn injuries and are now being treated at local medical facilities.
Two passengers, who are in critical condition, have been rushed to Lucknow for treatment, officials said.
The Uttar Pradesh government, meanwhile, has ordered a probe into the mishap.
Chief Minister Akhilesh Yadav has announced an ex-gratia of Rs.five lakh each for the families of the deceased while Rs.one lakh has been announced for those critically wounded and Rs.50,000 for those with minor burn injuries.
The ill-fated bus was going from Faizabad to Allahabad.
Initial reports said that a passenger, seated next to the conductor, was carrying a small LPG cylinder with him.
Uttar Pradesh Transport Minister Durga Prasad Yadav said strict action would be taken against any errant official once the probe is over.
"I am in Azamgarh and now headed for the scene of the mishap. Officials of Amethi acted promptly and we will fix responsibility. Anybody found wanting in his duties would be punished," the minister told IANS.
People of Saransipur village, where the incident took place, rushed towards the bus to douse the fire and save the passengers trapped inside, an eyewitness said.
Survivors said they heard a small explosion and tried to get out but the emergency door was locked. Some managed to escape by breaking the glass panes.
The bodies are yet to be identified.
