New Delhi, Feb 4 (IANS): Former IPS officer from West Bengal, Bharati Ghosh, on Monday joined the BJP here and termed Chief Minister Mamata Banerjee's 'dharna' a political move to stop the CBI investigation into the ponzi scheme scams.

Ghosh, once a favourite of Banerjee, reportedly fell from grace and sought voluntary retirement after she was transferred as Commandant of the West Bengal Armed Police's 3rd Battalion. Her application was accepted in January 2018.

Ghosh, a former police chief of West Midnapore district, joined the BJP in the presence of Union Law and Justice and IT Minister Ravi Shankar Prasad and BJP General Secretary Kailash Vijayvargiya.

She accused Banerjee of trying to block the CBI probe into the chit fund cases by holding a sit-in in Kolkata after the agency's officers on Sunday showed up near the residence of Kolkata police commissioner Rajeev Kumar, who has been under the scanner in connection with the CBI probe into the ponzi scheme scam.

"She should have held the 'satyagraha' when lakhs of people lost their money in the ponzy scams and committed suicide. Today she is doing it to protect a police commissioner. This is not 'satyagraha.' It is a political move to block the CBI probe," Ghosh told reporters.

"The chit fund mafias do not operate alone. They operate with the help of some people in the administration. Banerjee is hailing Rajeev Kumar as one of the best officers in the world. Then why the SIT led by him in Bengal could not arrest any of the actual culprits in the Saradha scam?" Ghosh asked.

In an unprecedented confrontation with the Modi government, Banerjee began a sit-in in Kolkata on Sunday, accusing the Centre of trying to run a parallel administration in states, saying there is a "constitutional breakdown" after an ugly face-off between the CBI and the state police.