Mumbai: Indrani Mukerjea, the prime accused in Sheena Bora's murder, had trained her then driver and co-accused Shyamwar Rai to communicate over video chat app Skype in a bid to avoid phone-tapping, the CBI said in its chargesheet, details of which emerged here on Wednesday.

The training was given to Rai by Indrani's secretary Kajal Sharma, who is now included as a witness in the murder case. Mumbai police had first made a reference to the use of Skype by the accused to communicate among themselves and the fact has now been corroborated in the CBI investigation.