Madhu, 55, was murdered by the two unidentified men using a blunt object at her own house in Khirki Extension area in south Delhi around 4.30 p.m., police said.
The attackers also injured her daughter-in-law who was present in the house, police said.
Police said the assailants seemed to be known to Madhu who let them into the house when they rang the door bell.
Madhu's daughter-in-law Rachna said she did not recognise the assailants, police said.
Rachna's husband Deepak was at his grocery shop at the time of the incident, said police.
Madhu's second son lived separately at another house, police said.
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