The Supreme Court on Tuesday asked the Central Bureau of Investigation (CBI) to come up with concrete evidence for custodial interrogation of ex-Kolkata Police Commissioner Rajeev Kumar in the Saradha chit fund scam. Kumar was earlier heading the West Bengal Police SIT probing the case. A bench comprising Chief Justice of India Ranjan Gogoi asked Solicitor General Tushar Mehta, who represented the CBI, to show that the request made by the probe agency on custodial interrogation was bonafide and was in interest of justice. It asked Mehta to come up with proof to corroborate if Kumar was even remotely part of destruction or disappearance of evidence in the scam. In his reply, Mehta told the top court that he will file the evidence against the former Kolkata top cop by Wednesday. The bench then listed the matter for further hearing on same day. The apex court was hearing the agency's appeal in which the latter had sought custodial interrogation of Kumar observing that that he had given evasive answers during questioning. Last month, the former Kolkata top cop had told the apex court that he was being targetted by the agency because of a larger conspiracy between two BJP leaders in the Saradha chit fund case. In his affidavit, Kumar had named BJP leaders Mukul Roy and Kailash Vijyawargiya behind a larger conspiracy. He had also told the top court that an audio clip is available in public domain in which both leaders are clearly heard of discussing "to target" some "senior police officers". Also read: Chit fund scam: CBI seeks Supreme Court permission to arrest top cop Rajeev Kumar "The sudden inexplicable turn by the petitioner\/CBI in pointing out problems with the investigation and targeting the alleged contemnor seems to be borne out of a larger conspiracy between two senior leaders Mukul Roy and Kailash Vijaywargiya of the BJP, the ruling party at the centre," the affidavit said.