According to police, the incident happened after deceased, Anuj, under the influence of alcohol, started abusing the accused -- Rohit.
Following the argument, the accused brought a knife and stabbed him. There was another person present in the room beside the two.
Thereafter, the landlord made a call to the police, and North Rohini police arrived at the spot.
The accused is from Jamshedpur in Jharkhand and was doing a computer course in Delhi after completing his BTech. Further investigation is underway.
( With inputs from ANI )