Police sources said the nurse, Sudesh Sharma, first stabbed to death her lovechild Aarav with a knife, then stabbed her daughter Komal, wrote a note with bloodstained hand saying Aarav was her lover's child, and then cooly called her lover's wife Reena Taneja to her home to set the stage of another murder.
Sudesh, police said, had a three-year-long extramarital affair with Manoj Taneja, a builder, who lived nearby. Sudesh's husband Anil Sharma works as external communications manager in the newspaper Pioneer.
Since last one and a half month, Manoj had been ignoring her, and for Sudesh, this was the last straw as Shakespeare wrote - 'Hell hath no fury than a woman scorned'. Sudesh hatched the plan to kill Aarav and Reena, and then commit suicide.
Police said, Sudesh first hacked her lovechild Aarav with a knife, then stabbed her daughter Komal and confined them to a room. She then called her lover's wife Reena Taneja on the pretext of discussing some matter.
Reena, police said, was not aware about Sudesh's intention. She reached her house, when Sudesh stabbed her in the neck and abdomen, killing her on the spot. 
Sudesh's husband Anil had bought the house five years ago from Reena's husband Manoj Taneja. Sudesh also had a 12-year-old daughter who was in school at the time of murders.
In her statement to police, Sudesh's daughter Komal said, when she came from school, her mother asked her to go straight to her room and sleep. "Normally she used to ask me to open my books and read", she said.
According to Komal, her other first killed Aarav sleeping in the bedroom, then came to her room and stabbed her. When Reena reached theeir home, Sudesh closed the door from inside, and stabbed her lover's wife in the face, neck and abdomen at least six times. A minute later, Sudesh stabbed herself, said Komal.
Komal, who was bleeding, managed to reach the balcony and screamed to neighbours for help. Neighbours rushed to the flat on the third floor, but the door was locked from inside. It was Sudesh, who was herself bleeding, managed to stand and open the door.
At the scene of crime, police said, Reena was lying dead outside the store room, Komal was lying in the balcony and Aarav lay dead on his bed.
Both Sudesh and her daughter Komal are undergoing treatment at AIIMS Trauma Centre. A case of murder and attempt to murder has been filed against Sudesh. She will be arrested after being discharged from hospital, police said.
The SDM on Saturday recorded killer Sudesh Sharma's statement at AIIMS Trauma centre, in which she said Aarav was her lover Manoj's son, and she wrote a note saying Manoj was responsible for all the deaths.
Delhi Police has recovered four knives from Sudesh's flat.
DNA samples of Aarav, Sudesh, Manoj and Anil have been collected for matching.
