Kumar, presently the Additional Director General, CID, was supposed to join duty on September 25 after being on leave since September 9, but did not attend office on Thursday and Friday.
A Central Bureau of Investigation (CBI) team went to Bhawani Bhavan, the CID headquarters on Thursday, but could not find the officer there.
The crack team of 12 officers brought from Delhi and Uttar Pradesh to track and nab Kumar, also failed to make much headway despite fanning out in Kolkata and the adjoining districts by splitting into small groups. They have searched guest houses, hotels, bungalows, hotels, a private hospital and even government offices, but Kumar managed to give them the slip.
On Thursday, ten members of the special team left Kolkata following orders from the headquarters.
Asked about Kumar's whereabouts, CBI Joint Director Pankaj Srivastava put the ball in the court of the state police.
"That can be known there (state police headquarters) only. How can we throw light on it?" Srivastava said.
Meanwhile, the Calcutta High Court's division bench continued to hold in-camera hearing on Kumar's anticipatory bail plea.
The bench of Justice S. Munshi and Justice S. Dasgupta will hear the case again on Monday.
Kumar, under the CBI scanner in the Saradha and Rose Valley ponzi scams, on Tuesday moved his anticipatory bail application before a division bench of the Calcutta High Court, alleging that the federal probe agency was "hounding" him.
Kumar headed the special investigation team (SIT) in 2013 that probed the ponzi scams, and is accused of tampering with evidence.
The Supreme Court had, in May 2014, handed over the case to the CBI.
( With inputs from IANS )