In the notice, Yadav asked Modi either to tender a public apology for this within one week or be prepared to face a criminal and civil case.
The notice served to the BJP leader by Yadav's lawyer Murari Kumar threatened to lodge a defamation suit of Rs one crore against him.
In the last Lok Sabha elections, Pappu Yadav defeated JD(U) president Sharad Yadav in Madhepura.
According to notice, he has always fought for poor and weaker sections of the society in course of which several cases were registered against him. But, no court has ever held him guilty, it added.
Sushil Modi, who is Leader of Opposition in Legislative Council at present, has been describing Yadav as a man of criminal background in interviews and comments in media which has been denting image of the MP, the notice, a copy of which was made available to media persons, said.
The RJD MP alleged that he has been undergoing mental stress due to sustained 'sinister' campaign of Sushil Modi against him.

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