Cases were lodged on Friday at the Kunda police station against the manager of the hermitage (ashram) where 63 people died in a stampede on Thursday.
The organiser of the feast (bhandara) at the ashram has also been booked.
However, no individual has been named in the first information report (FIR). Kunda is 75 km north-west of Allahabad.
Pratapgarh SP Mahesh Mishra said: “Once we identify the culprit, an FIR will be registered against him.”
When an FIR has been filed, the police are legally bound to investigate a case.
The police said Kripalu Maharaj, who runs the ashram, was in the hermitage itself. But he was not accessible to the media.
The spokesman of the hospital at the ashram, K.P. Singh, said God was responsible for the deaths.
“We did not invite the people to the bhandara and do not know from where the 25,000 people came,” an ashram official said.
The devotees had gone there in the hope of getting good stuff to eat and collecting gifts such as utensils, clothes and cash. There the stampede took place.
Purai (85) lost four members of his family. They were cremated at Manikpur Rajghat, 20 km from the ashram.
Of the 63 killed, 22 were cremated at the Manikpur Rajghat.
Official apathy, seen on Thursday in not managing the crowd well at the hermitage, was once again evident on Friday. No arrangements for the big cremation were made. Locals say the district administration could not even provide adequate firewood for the cremation.
Pratapgarh District Magistrate C S Verma said: “The villagers received Rs 10,000 from the ashram trust for the cremation. Policemen and magistrates were posted at the cremation site and other places.”