The posters had claimed that Rahul Gandhi will usher in Ram Rajya in the country.
Three persons, including a local Congress leader, were booked by the police in connection with the anti-Modi posters that appeared in Amethi recently, officials said today.
The posters were seen near the Gauriganj railway station, and a case has been registered in this regard at the Gauriganj police station, Additional SP, Amethi, BC Dubey said.
"We have registered a case against Abhay Shukla, Narendra Singh and Ram Kumar under various sections of the IPC. Police is investigating the matter and action will be taken against the guilty," he said.
Narendra Singh is a local Congress leader, police officials said.
The BJP had yesterday demanded an apology from the Congress president Rahul Gandhi for the posters in his Lok Sabha constituency Amethi which it claimed "denigrated" Prime Minister Narendra Modi.
Senior BJP leader and UP cabinet minister Shrikant Sharma said, Rahul Gandhi must apologise before the entire nation for the "insulting poster".
In a statement issued here, Sharma had claimed, "It is at the behest of Rahul Gandhi that his sycophants had shown the PM as Ravana in the poster. The Congress is intolerant towards Modiji. Former Congress president (Sonia Gandhi) had called Modiji "maut ka saudagar" (merchant of death)".
The posters had claimed that Rahul Gandhi will usher in Ram Rajya in the country.