The following is the chronology of events in the Aarushi Talwar murder case:
Aarushi's body is discovered in her Jal Vayu Vihar apartment in neighbouring Noida.
Hemraj, the family's domestic help named the prime suspect.
Hemraj's body found on the terrace of the apartment.
Noida police say murders committed with surgical instrument.
Investigating officer shifted.
Aarushi's mobile phone untraceable.
The Talwar family's former servant, Vishnu Sharma, named the prime suspect.
Police interrogate Vishnu and also search the garage of the Talwar home.
Sleuths of Delhi Police's Crime Branch join the murder probe.
Aarushi's dentist father Rajesh Talwar arrested.
Inspector General of Police (Meerut range) tells reporters Aarushi was killed after Talwar found her in an "objectionable but not compromising position" with Hemraj.
Aarushi's dentist mother Nupur Talwar claims her husband is innocent.
Family visits Rajesh Talwar in jail.
Talwar's home searched.
Shocked friends decry "false stories" about Aarushi.
Talwar's lawyer Pinaki Mishra demands a Central Bureau of Investigation (CBI) probe.
Court grants police Talwar's custody for three days.
A child rights panel seeks an explanation from Noida police for its "objectionable" statements on Aarushi.
Aarushi's schoolmates protest character assassination.
Talwar's lawyer Abhijeet Banerjee files a contempt petition in a court against Noida police for not allowing him to accompany his client when he was taken into police custody.
Investigating officer changed for the third time.
Uttar Pradesh Chief Minister Mayawati demands CBI probe into the double murders.
Talwar returns to court custody.
CBI takes over the investigations; questions Aarushi's mother.
Mayawati shunts out all the senior police officers connected with the investigations till then.
Talwar in CBI custody for a day.
CBI gets Rajesh Talwar's custody for two more days.
Talwar subjected to lie-detector test.
Talwar sent to 14 days' judicial remand.
Minister for Women and Child Development Renuka Chowdhury demands that the senior police officers who made "derogatory remarks" against Aarushi must apologise.
CBI searches sewer lines near Talwar's home for murder weapon but is unsuccessful.
Talwar's bail plea deferred.
"It is impossible that the Talwars did not hear Aarushi's cries", CBI says.
Nupur Talwar protests to child rights commission against TV serial on Aarushi; panel agrees, saying Aarushi tragedy no soap opera.
CBI has no firm leads in case.
Talwar's compounder Krishna undergoes lie-detector, psychological test.
CBI conducts fresh search at Talwar's residence; says murders pre-meditated.
Talwar denied bail.
Compounder Krishna emerges as prime suspect.
CBI takes Krishna to Bangalore for narco-analysis.
Krishna's lawyer beaten up in CBI court for violating strike call.
Krishna undergoes narco-analysis test.
CBI arrests Krishna.
CBI conducts psychological test on Talwar.
CBI searches home of Talwar's friends Anita and Praful Durani; searches water tanks on the roof of Aarushi's apartment.
Krishna in CBI custody for three days.
Aarushi's mother put through lie-detector test.
Reports of Nupur Talwar's imminent arrest are speculative, says CBI.
Talwar's apartment searched again.
Krishna has confessed to the crime, CBI says; gets his custody for six days.
Krishna merely a witness, insists lawyer.
CBI quizzes doctors who conducted Aarushi autopsy.
Duranis undergo psychoanalysis test.
Talwar's custody extended by 14 days.
June 20: Talwar undergoes second polygraph test.
CBI quizzes Noida police officers who investigated case.
Talwar maintained during lie-detector tests he was innocent, CBI says.
Talwar is very depressed and his medical condition has worsened since his arrest, Nupur Talwar says.
CBI gets four more days to grill Krishna.
Aarushi's mother Nupur Talwar interrogated.
Nupur Talwar subjected to lie-detector test.
Talwar's bail plea rejected.
CBI recreates crime scene at Talwar's residence.
Durani's domestic help Rajkumar arrested; forensic test reveals that bloodstained T-shirt recovered June 13 from his room had blood stains of human origin.
CBI officials seize Rajkumar's bicycle after bloodstains were found on it.
Rajkumar sent to 14 days CBI custody.
Krishna's bail plea rejected.
Talwar's custody extended till July 11.
CBI quizzes Nupur Talwar.
Supreme Court dismisses petition by a lawyers' body questioning the use by CBI of crime detection techniques like brain mapping and narco-analysis.
CBI denies reports circulating the previous day that the Talwars were not at home on the night of the murder.
CBI conducts second narco-analysis on Rajkumar.
CBI exonerates Talwar; says Krishna and Rajkumar killed Aarushi and Hemraj.
Rajesh Talwar gets bail, discharged.