CBI sources said the agency was initially reluctant to take over the probe as the case was almost solved by Delhi Police but after going through available material it was decided that there was scope of investigation.
"We have decided to take over the probe in the killing of Nido Tania and a case would be registered soon after completing the formalities," a senior CBI official said.
The sources said the decision to take over probe has been communicated to Department of Personnel and Training which would issue the notification.
He was found dead the next day at his residence. Delhi Police has already slapped murder charges against four persons in connection with the case. The police had informed a local court that it booked accused Farman, Sunder, Pawan and Sunny Uppal under section 302 (murder) of IPC after the postmortem report revealed that Tania died of injuries to his head and face caused by a blunt object.
Former Delhi Chief Minister Arvind Kejriwal had also recommended a magisterial inquiry into how Tania died following an assault on him and what was the response of the law enforcing agencies.