Bangalore: Two months after the arrest of mining baron and former Karnataka Minister G. Janardhana Reddy on charges of illegal mining, a formal probe into the role of his wife Aruna Lakshmi in the scandal began on Saturday.

The Central Bureau of Investigation, which arrested Reddy on September 5 registered a First Information Report (FIR) against Aruna Lakshmi, a requirement under law to begin formal investigation in a case, agency sources said.

Aruna Lakshmi owns, along with her arrested husband, the Associated Mining Company (AMC), whose main office is in the iron-ore rich Bellary district, about 300 km from Bangalore.

The couple also owns the Obulapuram Mining Company (OMC), which has its main office in Anantpur town in neighbouring Andhra Pradesh.

Reddy is in Hyderabad's Chanchalaguda jail in connection with illegal mining in Andhra Pradesh.

The FIR against Aruna Lakshmi, registered in Bangalore, came a month after CBI teams raided the AMC offices in Bellary and registered an FIR against Reddy, for the first time in Karnataka.

Along with Aruna Lakshmi, 20 others are also being probed, the sources said but declined to give the names.

AMC, Aruna Lakshmi and others are under scanner following September 23 Supreme Court directive to CBI to investigate the linkage between the multi-crore-rupee illegal mining in Bellary district and Anantapur district in Andhra Pradesh, allegedly involving Reddy.

According to CBI, the iron ore mined by AMC was routed through OMC.