The CBI started investigating the case on the directions of the Allahabad High Court in January this year.
A senior Central Bureau of Investigation (CBI) official told : "Several CBI teams started the searches at over 22 places in Uttar Pradesh this morning. The CBI team also raided three residential premises of former UP minister Prajapati in Amethi."
The agency had on January 2 registered a case against 11 people under sections of the Indian Penal Code and the Prevention of Corruption Act.
The agency has named former Hamirpur District Magistrate B. Chandrakala, miner Adil Khan, geologist/mining officer Moinuddin, Samajwadi Party (SP) leader Ramesh Kumar Mishra and his brother Dinesh Kumar Mishra among the accused.
Also named are former Mining Department clerks Ram Ashray Prajapati and Ram Avtar Singh, as well as Sanjay Dikshit, who contested the 2017 Assembly polls on Bahujan Samaj Party (BSP) ticket, and his father Satyadeo Dikshit.
On January 5, the CBI carried out searches on 14 locations in Delhi and Uttar Pradesh, including the residences of Chandrakala as well as a SP and a Bahujan Samaj Party leader in connection with the case.
Former Chief Minister and SP chief Akhilesh Yadav held the Mining portfolio in the state from 2012 to 2013. Prajapati succeded Yadav as the Mining Minister.
( With inputs from IANS )