Bangalore, Sep 14 (IANS) Enlarging its enquiry into illegal mining by mining baron G. Janardhana Reddy, the Central Bureau of Investigation will Sep 16 interrogate his elder brother G. Karunakara, agency sources said late Wednesday.

"Karunakara Reddy has been summoned to appear before CBI in Hyderabad on Sep 16," the sources said.

Karunakara's interrogation would come 11 days after the arrest of Janardhana, former Bharatiya Janata Party minister in Karnataka, for illegal mining in Andhra Pradesh by his Obulapuram Mining Company.

Karunakara, who was also minister in the B.S. Yeddyurappa government, was a director of OMC but has said he quit the post in 2004.

Janardhana was arrested by CBI on Sep 5 from Bellary in north Karnataka bordering Andhra Pradesh. He is now under CBI custody in Hyderabad. Also arrested with him was OMC managing director B.V. Srinivas Reddy.

The CBI may also question Reddys' associate B. Sriramulu, who was health minister in the Yeddyurappa cabinet.

Sriramulu was also OMC director and says he quit the post in 2008.

The former Lokayukta (ombudsman) N. Santosh Hegde had indicted the two Reddy brothers and Sriramulu in his report on illegal mining scam.

The Congress has been demanding immediate arrest of Karunaraka and Sriramulu on the ground that they could tamper with evidence.