The Enforcement Directorate (ED) arrested West Bengal police officer Ashok Mishra in connection with the coal pilferage case, officials said on Sunday.
Mishra, the inspector-in-charge of the Bankura police station, was arrested on Saturday night from Delhi, they said.
He is alleged to have links with Anup Majhi, alias Lala, who is considered to be the kingpin of the scam, sources said.
This is the second arrest in the case, the probe for which began in November last year.
The agency had earlier arrested Bikash Mishra, the brother of Trinamool Congress youth leader Binay Mishra, in connection with the case.
Binay Mishra has been evading interrogation, following which a look-out circular was issued against him, officials said.
Majhi, the alleged kingpin, is scheduled to appear before the CBI on Monday for interrogation. He has been interrogated twice so far after being elusive for long.
The investigating agency on November 28 last year carried out a massive search operation in a number of locations in four states — West Bengal, Bihar, Jharkhand and Uttar Pradesh — after registering a case against Majhi.
The CBI had acted on information from “reliable sources” indicating illegal excavation and theft of coal in the leasehold area of Eastern Coalfields Limited in “connivance” with the officials of ECL, CISF and Railways.
The CBI team on February 23 visited the residence of Trinamool Congress MP Abhishek Banerjee and examined his wife Rujira in connection with the case. The agency also examined Rujira”s relatives on the same matter.
Abhishek is the nephew of Chief Minister Mamata Banerjee.
The ED is probing the money laundering aspect of the alleged scam, officials said.