The federal agency also undertook some searches in Ranchi against a person named Antu Tirkey, who is allegedly linked to the case.

The arrested person identified as Afshar Ali was lodged in jail under judicial custody in another money laundering case and the agency has taken his custody in the latest case after seeking a designated court's permission.

Ali is accused of committing "forgery" for allegedly grabbing some land in Jharkhand in purported connivance with the prime accused in the case against Soren and former revenue department sub inspector Bhanu Pratap Prasad.

This is the fourth arrest in the instant case.

The 48-year-old JMM leader Soren was arrested by the ED in January shortly after he resigned as the CM. He is currently lodged at the Birsa Munda jail at Hotwar in Ranchi under judicial custody. Prasad and one Mohammed Saddam Hussian have also been arrested.

The probe against Soren pertains to an 8.86 acre land in Ranchi that the ED has alleged was illegally acquired by the former CM.

A charge sheet was filed by the ED against Soren, Prasad, Soren's alleged "frontmen"--Raj Kumar Pahan and Hilariyas Kachhap and an alleged associate of the former CM, Binod Singh, on March 30 before a special Prevention of Money Laundering Act (PMLA) court here.

The ED has also attached the Ranchi land and requested the court for confiscation of the 8.86-acre plot.

The money laundering investigation stems from multiple FIRs registered by the Jharkhand Police in land "scam" cases against several persons, including state government officials.

The prime accused in the case is Prasad, also a custodian of government records, who is alleged to have "misused" his official position by providing assistance to several persons including Soren in their activities linked to illegal occupation, acquisition and possession of proceeds of crime in form of landed properties, the agency had said in a statement.

"A racket of land mafia is active in Jharkhand which used to forge the land records in Ranchi," it has claimed.