Gujarat high court, hearing contempt petitions against chief minister Narendra Modi, on Wednesday asked the state government to find out who leaked a letter written by him to prime minister Manmohan Singh which had confidential information on the Lokayukta issue.

A division bench of justices Akil Kureshi and Sonia Gokani asked the state advocate general to find out who leaked his letter and whether he was aware of it (giving the letter for publicity).

Two separate contempt of court petitions were filed in the high court against Modi -- one by Bhikhabhai Jethva, father of murdered RTI activist Amit Jethva, and the other by a lawyer representing NGO Jan Sangarsh Manch.

Both of them contended the confidential letter was leaked to the media by the state information department, when the case related to the appointment of Lokayukta was pending before the high court, which is contempt of court.

The court will now hear the case on September 21.

Appearing for Jethva, advocate Anand Yagnik said that Modi by "consciously disclosing the letter written to the prime minister on the subject matter of the ongoing judicial proceedings and making it public has deliberately committed criminal contempt".

In the letter, Modi levelled serious allegations against Lokayukta R A Mehta, the governor, the leader of opposition and even the chief justice of Gujarat high court. He had also revealed communication between him and all the others deliberately, Yagnik told the court.