"The investigation is on and we have seized some documents. It includes the post- mortem reports of the entire 2008 year," said a senior CBI official requesting anonymity.
According to the officials, the procedure of autopsy reports would be compared to Aarushi's report to find out if "due procedure" was followed.
Aarushi was found murdered in her parents' Jalvayu Vihar apartment on May 16, 2009. The family's domestic help Hemraj, who was initially suspected to be the accused, was found murdered a day later on the terrace of the house.