The Delhi Police took Sahil Gehlot, accused of killing his girlfriend, to the crime spot on Thursday to recreate the sequence of events leading up to the incident.
Police have also found out that the accused had deleted chats and other data from the victim's mobile phone after the incident, officials said.
Police also took Gehlot to his dhaba (eatery), where he had allegedly kept the body of his girlfriend Nikki Yadav (23) inside a refrigerator.
The victim's family has demanded that the trial of the accused be held in a fast-track court.
Gehlot was taken to the crime scene in north Delhi's Kashmiri Gate area, where he had allegedly strangulated Yadav to death inside a car with a mobile phone cable. Subsequently, Gehlot was taken to the dhaba.
Police are scanning the CCTV footage obtained from nearby areas and have also summoned Gehlot's brother Ashish for questioning. The car used in the commission of the crime belonged to Ashish, sources said.
Police will also take Gehlot to the Nizamuddin and Anand Vihar railway stations, where he had taken the victim in the car on the fateful day. The sequence of events is being recreated to ascertain the exact place and time of Yadav's killing, the sources added.
The incident came to light on February 14, four days after the crime was committed, when Gehlot confessed to the crime in police custody and led police to the refrigerator in his eatery where the victim's body was hidden.
The post-mortem examination of the body went on for more than two hours at the Deen Dayal Upadhyay hospital here on Wednesday and according to the doctors' preliminary opinion, the cause of death was strangulation.
The victim and the accused had a fight around 20 metres away from the Nigambodh Ghat, following which he killed her, the sources said.
With her body lying beside him, Gehlot deleted the data from Yadav's phone and drove to his dhaba. He drove through the Majnu ka Tila bypass, the Madhuban chowk, Paschim Vihar, Janakpuri and Uttam Nagar to reach Mitraon village, the sources added.
Gehlot wanted to marry Yadav, but his family members were against it. They wanted him to marry a woman of their choice, the sources said.
Police have confiscated Yadav's mobile phone from Gehlot's possession and it will be sent for a forensic examination so that the deleted data could be retrieved, they added.
Meanwhile, the victim's uncle, Praveen Yadav, accused police of "misleading" the family and the public. He also demanded that Gehlot "should be hanged".
"The case should be heard by a fast-track court and the culprit should be hanged. Police are trying to mislead us. Nikki was living in a hostel, she was not in a live-in relationship," he claimed.
He further claimed that after the victim went missing, her father had approached Gehlot but was not given any information by the accused.
The National Commission for Women (NCW) has sought a report from the city police on the incident.
Sources in the NCW said the women's panel has sought the report from the police commissioner.
"How heartless a person can be? Not only he killed his live-in partner but got married to another girl the same day. What is the role of parents that we need to look into also have to work out on the mindset of families who think children are their properties," NCW Chairperson Rekha Sharma said in a tweet.
According to police, Gehlot had never told Yadav that he was engaged to another woman and when it was finally revealed to her, the two had a row that led to the accused killing her.
After killing Yadav, Gehlot allegedly stuffed her body inside a refrigerator at his dhaba in southwest Delhi and went for his wedding the same day.