The city police on Sunday arrested the remaining three accused in connection with the murder of a 50-year-old woman in Luxman Vihar.
The victim, Manjeet Kaur, was allegedly killed by her nephew on Saturday night.
The police had also recovered the knife used in murder, clothes which bore blood stains and the car driven by the main accused.
The three arrested, including main accused Ravinder Singh, his wife Sonia and 65-year-old grandmother Nabh Kaur, were sent to 14 days' judicial custody on Monday at a local court.
On Saturday night, the Sushant Lok-based property dealer had killed his aunty and injured his cousin.
"The trio had got themselves admitted to a private hospital in Sushant Lok to evade arrest," said inspector Harinder Singh, SHO, Sector 5 police.