"We have registered a case under sections 302 (murder) and 307 (attempt to murder) of the IPC against Sudesh," said a police officer.
Sudesh, 36, is the wife of Anil Sharma, who works as a librarian with the Delhi-based newspaper.
Police said Sudesh had Thursday killed Reena Taneja, the wife of builder Manoj Taneja in her house in Moti Nagar in west Delhi.
She also killed her own son, Aarav, three, and attacked her daughter before injuring herself. Her daughter Komal, 17, is out of danger.
According to Deputy Commissioner of Police Ranveer Singh, Reena, 44, entered the librarian's house and engaged in a heated argument with Sudesh over some issue.
"During the argument, Sudesh attacked Reena with a sharp-edged weapon that led to Taneja's death. Later, she stabbed her own son, Komal and herself," Ranveer Singh told IANS.
Police are exploring an extra marital angle in the murders.
"Sudesh attacked her own son and daughter because she was worried as to who would take care of them after her death," said the officer.
The officer said Sudesh, who is undergoing treatment but out of danger, will be arrested after she is discharged from the hospital.
--IANS (Posted on 18-10-2013)