New Delhi: The Central Bureau of Investigation (CBI) is poised to step up its scrutiny of the alleged involvement of former Union finance minister P. Chidambaram and his son Karti in the INX Media case, persons familiar with the development said.

The same persons claimed that the CBI may, in the next fortnight, even summon P. Chidambaram for questioning. In addition, to the INX Media case, the CBI is also taking up four other instances of alleged irregularities in Foreign Investment Promotion Board (FIPB) clearances under Chidambaram referred to it by the Enforcement Directorate (ED).

While P. Chidambaram declined comment, Karti Chidambaram said, “All allegations against me are wild and reckless."

While the court extended Karti Chidambaram’s CBI custody till 9 March in the INX Media case, his bail application, which was filed on 5 March, will also be heard on 9 March by the same court.

At the same time, while INX Media director Indrani Mukerjea as well as Karti Chidambaram had been jointly quizzed by the CBI on Sunday in Mumbai’s Byculla jail, the ED questioned the other director of INX Media—Peter Mukerjea—for six hours at Mumbai’s Arthur Road jail on Tuesday.

However, senior CBI officials, who did not wish to be identified, stated that the agency would now push for Peter Mukerjea’s custody in order to quiz him in the INX Media case.

Karti Chidambaram was sent to police custody for one day on 28 February, which was extended by five days on 1 March, by the special CBI court in New Delhi.

Additional solicitor general (ASG) Tushar Mehta appearing for CBI asked for an extension of remand by another nine days on grounds that out of the six days’ custody, CBI had “virtually four days" to interrogate Karti Chidambaram who was “evasive" and “uncooperative".

Mehta informed the court that the investigating agency had unearthed new and significant “materials" that demanded further custodial interrogation. The details of these new “materials" were given to the judge in a sealed envelope.

It was further clarified that Indrani Mukerjea’s testimony that she along with her husband had met Karti to get clearance from the FIPB for INX Media, was not the sole evidence they possessed.

Abhishek Manu Singhvi, appearing for Karti Chidambaram, argued that no extension of police custody could be granted as there was no “real necessity" for the custody to continue. Arguing that police custody was an exception and not the rule, he stated that CBI did not necessarily need to keep him in custody to interrogate him. Instead, Singhvi argued, that CBI could ask Karti Chidambaram to appear every day at a specified time for questioning.

He further submitted that an accused is constitutionally protected under Article 22 and Article 21 from answering questions put forth by an investigating agency and such refusal could not form grounds for extension of police custody.

Karti Chidambaram has been accused of having received Rs10 lakh in kickbacks in 2007 to clear foreign investment worth Rs305 crore for INX Media, which was owned by Peter and Indrani Mukerjea, at a time when P. Chidambaram was finance minister under the first United Progressive Alliance (UPA) government.

INX Media is being probed by both CBI and ED over the allegations that Karti Chidambaram had received kickbacks from the media house.