The CBI has arrested former Bihar chief minister Lalu Prasad's aide Bhola Yadav in connection with the "land-for-jobs" scam in the railways when Prasad was the railway minister in the UPA government, officials said on Wednesday.

The Central Bureau of Investigation (CBI) also conducted searches on Wednesday at four premises -- two each in Darbhanga and Patna -- belonging to Yadav, who was the officer on special duty (OSD) to the then railway minister Prasad between 2005 and 2009, they said.

Yadav, fondly referred to as "Hanuman" or the "shadow" of Prasad among Rashtriya Janata Dal (RJD) supporters, was questioned by the CBI in connection with the scam, in which land measuring over one lakh square feet belonging to job aspirants' families in Patna was allegedly purchased or transferred to Prasad's family members in return for group-D jobs in the railways.

The CBI suspects that Yadav had played a crucial role in facilitating the jobs and later, the transfer of land to Prasad's family.

Considered to be Prasad's "man Friday", Yadav had taken a plunge in electoral politics and won the Bahadurpur seat in Darbhanga in the 2015 Bihar Assembly polls on an RJD ticket.

He decided to change the seat in 2020 to Hayaghat in the same district, a decision that proved to be costly as he lost the polls.

The CBI had filed the FIR on May 18 against Prasad, his wife Rabri Devi, daughters Misa Bharti and Hema Yadav, in addition to 12 people who were given jobs in the railway zones of Mumbai, Jabalpur, Kolkata, Jaipur and Hajipur, the officials said.

The agency has alleged that land measuring about 1.05 lakh square feet in Patna was acquired by Prasad's family members by making payments to the sellers in cash.

"The current value of the above said seven parcels of land, including the land acquired through gift deeds, as per the existing circle rate is about Rs 4.39 crore.... Enquiry has revealed that the parcel of land, which was directly purchased by the family members of Lalu Prasad Yadav from the sellers, was purchased at lower rates than the prevailing circle rates," the FIR has alleged.

It said people were appointed in the railways without any advertisement or public notice issued for the purpose on the basis of forged documents.

The agency had also carried out searches at Prasad's residence in Patna and other locations on May 20.

"We reiterate that the latest CBI case and the raids conducted across the country in connection with the same are sponsored by the Bharatiya Janata Party (BJP), which rules at the Centre," the RJD had alleged after the searches.