Abdul Rehman, a Jamia Nagar resident and main accused, along with Nadeem Khan, 32, of west Delhi's Nangloi were arrested on Monday after Rehman broke down during sustained interrogation and confessed to his crime. Nadeem was arrested later.
One accused Guddu is still at large.
Rehman had roped in Nadeem and Guddu with a promise of Rs 2.5 lakh for killing his father Shamim, 55, and mother Taslim Bano, 55, in Jamia Nagar.
"During interrogation, Rehman told police that he is already married and used to work at a call centre but left in 2016 due to his drug addiction. He met a girl on Facebook, who stayed in Uttar Pradesh's Kanpur," Deputy Commissioner of Police Chinmoy Biswal said.
Police said Rehman along with Nadeem and Guddu smothered Taslim Bano and Shamim on April 28 while they were asleep at their house.
After Nadeem and Guddu escaped from the spot, Rehman somehow locked the door from inside and later concocted a story that his parents were killed by robbers, the officer added.
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