The family's domestic help Hemraj, who was missing and was initially suspected for her killing, was found murdered a day later on the terrace of the house.

The sensational case has remained an unsolved riddle.

All those who were picked up for interrogation in the initial weeks of the murder - Aarushi's dentist-father Rajesh Talwar, his medical assistant Krishna and two other neighbourhood domestic helps Raj Kumar and Vijay Mandal - have been freed after a period of detention while the CBI still continues to hunt for material evidence.

Despite an intense search, the agency had not been able to locate the mobiles of Arushi and Hemraj and the weapon used to slit the two victims' throats.