On the first floor of the house in Rohini Sector 17, where three people were found murdered on Friday morning, the police found two suitcases on a table.
These suitcases were the only items that the police found ransacked in the double-storey residence.
Sources said this supported the police's theory that the deaths were not mere murders during a robbery gone wrong.
The police said the assailant(s) had tried to destroy evidence in the house and that they probably had a friendly entry into the house of the victims, who were usually extra cautious about their security.
But senior officers maintained that it was too early to reach a conclusion about how the murders happened.
Jolly, the elder sister of victim Karishma alias Rozy, has pointed fingers at her sister Hema's separated husband who is an advocate in Bikaner, Rajasthan. She told the police that their divorce case, which was pending in a city court, was finalised after Hema's husband gave R2.5 lakh as settlement to her parents.
Hema had left her husband around 13 years ago and had started living with her parents. Sources said Hema moved to a rented accommodation in Sector 28 15 days back. Investigators are asking Hema as to why she shifted.
Rozy and her mother Rekha Chauhan, 52, were found strangled to death in their first-floor bedroom floor while her father Yogendra Pratap Singh Chauhan, 52, was found in a pool of blood on his bed on the ground floor.
"We are waiting for the autopsy reports to ascertain the exact cause of the deaths," said Tejendra Luthra, joint commissioner of police (northern range).
Naresh Gupta, a neighbour of the victims, said Rekha was supposed to go on a trip to Vaishno Devi with 10 other women in their colony.
Around 6.30am, local priest Uday Chand Jha, who had organised the trip, knocked at the main iron door of the victims' house because the group was getting late but he got no response.
"When he got no reply, Jha asked his wife and daughter to help. Later, they realised that the main doors of the house were not latched and they
then found the bodies. The police were immediately called," Gupta said.
Police later found that Rozy's laptop, her mobile phone and her father's mobile phone were also missing.
"Nothing but the two suitcases were ransacked. The assailants had also washed the floor of the first-floor bedroom with water and a hand duster," said a police officer.
Rozy completed her mass communication course from a private media institute before doing internship in a news channel in Noida.
She is survived by her elder sisters Jolly and Hema and her sister-in-law Renu, who lives at her parents' house along with her 4-year-old after the death of her husband, Vikram Singh Chauhan, in an accident.