Even as the Central Bureau of Investigation digs deeper and deeper into the Aarushi-Hemraj murder case, the T-shirt allegedly belonging to one of the accused, Rajkumar, will play a crucial role in cracking the case.

The T-Shirt with blood stains allegedly belonging to Rajkumar, Anita Durani's domestic help, is at present with the Centre for Finger Printing DNA and Diagnostics at Hyderabad.

A source in the investigating agency said that it has been confirmed that the blood stains on the T-shirt are not Rajkumar's.

After Rajkumar had been arrested, it was alleged by him initially that the blood stains on the T-shirt were his.

It was said that he had bruises on his body thanks to an allergy and that may have caused the blood stains.

The CDFD is trying to ascertain now whether the blood stains were of Aarushi and Hemraj.

The CDFD is yet to complete the verification process and sources say that it may take another day or two before they come to any sort of conclusion.

Rajkumar was picked up by the CBI based on the results of the narco-analysis tests conducted on Krishna, the compounder at Dr Rajesh Talwar's clinic.

Krishna, during the test conducted at Bengaluru, had said that the motive was two-fold. Firstly, Krishna had sought to take revenge on Dr Talwar who had allegedly humiliated him for goofing up at the clinic.

Secondly, it was alleged that Rajkumar had tried forcing himself on Aarushi and when she resisted, he killed her fearing that he might get exposed.

Hemraj, the domestic help at the Talwars, was murdered two as he threatened to expose both Krishna and Rajkumar for committing the murder.

Although the tests make no mention of Dr Talwar's role in the murder, the CBI is not ready to give him a clean chit as yet.

They say that the investigations are still on and they are not ready to free Dr Talwar as yet. During Krishna's interrogation, it was stated that Dr Talwar, who is now in judicial custody, had no role to play in the murder and he was fast asleep in his room when the incident occurred.

The CBI is now trying to ascertain whether Dr Talwar was part of a conspiracy and also how he did not hear anything when the double murder and the attempted rape took place, considering the fact he was in the next room.