The bodies of a 60-year-old woman and her daughter were found at their house in outer Delhi's Mianwali Nagar area on Saturday morning, police said.
They were identified as Shashi Talwar and her daughter Nidhi, 40, who was differently-abled.
The incident came to light after their maid returned to work on Saturday morning, the police said, adding that she rang the doorbell several times, but when there was no response, she entered the house from the other door.
She found the two lying in a pool of blood and informed the police at around 10 am.
Shashi Talwar's throat was slit while her daughter Nidhi was attacked with a blunt object, they said.
The police said they do not suspect any robbery or theft angle to the twin killings. The reason the police gave for this was that their jewellery was found intact.
Ms Talwar's husband had died two years ago due to a heart attack.
It is suspected that someone known to the family carried out the killings since there were teacups lying in the drawing room, the police added.
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