Brushing aside allegations against advocate and former union minister Shanti Bhushan and his son Prashant Bhushan, Bihar chief minister Nitish Kumar on Monday said the smear campaign against the anti-corruption activist Anna Hazare, Shanti Bhushan and his advocate son would boomerang.

"As long as I know, the integrity of both Prashant Bhushan and Shanti Bhushan is intact.... It will rather boomerang on those who are engaged in malicious campaign against Anna, father and son," Kumar told reporters during his Janata Darbar programme.

In a similar vein, he said both Shanti Bhushan and his son were competent enough to tackle and give a befitting reply to those being behind the campaign.

"Those who are levelling such allegations seem to be dialling a wrong number," he said without naming anyone.

"I recall that sinister attempts were made to malign former Prime Minister V P Singh in the St. kitts case. But ultimately nothing was found," he said.

Prashant Bhushan, who is a member of the newly constituted 10-member draft committee of the Lokpal Bill along with his father Shanti Bhushan, has decided to move a criminal contempt petition in the Supreme Court about a purported telephonic conversation between him, SP chief Mulayam Singh Yadav and expelled SP leader Amar Singh, which showed attempts at influencing a judge.