A Delhi court today sent Chief Minister Arvind Kejriwal's former Principal Secretary Rajendra Kumar and six others to three-day CBI custody. They were earlier arrested in an alleged corruption case. A Special CBI Judge Arvind Kumar sent Rajendra Kumar and six others to the CBI custody after they were produced before it on expiry of their one-day judicial remand. <br/><br/>During the hearing, the CBI said six more addresses were revealed during the interrogation from where several more incriminating materials were recovered. It also claimed that during the search, a diary was recovered which suggested that 60 lakh rupees cash was paid by one of the accused to acquire a flat for another accused. Besides it, The CBI also told the court that some of the accused persons were threatening the witnesses and asking them not to cooperate in the investigation.