Leader of opposition in West Bengal Suvendu Adhikari on Monday wrote to Prime Minister Narendra Modi "expressing concern" that the CBI was not acting against those holding high positions and involved in the decade-old Saradha chit fund scam.

In his letter, Adhikari alleged that Chief Minister Mamata Banerjee was the "biggest beneficiary" of the scam involving crores of rupees but the CBI was hesitating to act against her because of her post.

Hitting back, the Trinamul Congress alleged Adhikari, who was a minister in Banerjee's cabinet before joining the BJP, himself was named in a declaration by Saradha chief Sudipta Sen as one of the main beneficiaries of the scam.

Adhikari, in the letter, alleged, "The CBI was handed over the responsibility of the investigation, because it was a scam which involved thousands of crores collected from the public allegedly because of the patronage of people occupying high positions in the system." "The CBI was expected to nail the person occupying the highest position in the system," he wrote.

Adhikari alleged that Banerjee's association with Saradha goes back to the time when she was the railway minister in the UPA-2 government.

"Is this why the CBI is hesitant? Or has the height of her chair made them reluctant to act against her? But wasn't it the primary reason for handing over the investigation to the CBI? So that the position of the high & mighty doesn't deter them from acting against them and bringing them to justice," he said.

TMC spokesperson Kunal Ghosh told PTI that Adhikari joined the BJP "to wash the stains of his corruption".

"Adhikari should not hurl stones while living in a glasshouse. He was named by Saradha chief Sudipta Sen as one of the main beneficiaries," he said.

"Adhikari got into the washing machine of the BJP for washing the stains of his corruption. It is clear that he is not ashamed of himself. Why are the agencies not acting against Suvendu? The central agencies are showing a bias towards him," Ghosh added.

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