According to police, Sonu Mistry alias Rajender Prasad, who was working as a servant with the victims for the past 12 years, was upset over the behaviour meted out to a female employee he was close to.
Rajkumar and Devinder Manchanda were found bludgeoned to death at their office premises in Ram bazar area on February 11.
Sonu was working with them for the last 12-13 years and was their most trusted employee, police said.
Sonu had also been at the receiving end of the abusive and humiliating behaviour of his employers, they said.
Sonu, who was in an inebriated condition, killed Rajkumar with a chopper on the fateful day. He later called Devender on the same floor claiming that Rajkumar was calling him and then murdered him as well, police said.
The accused then fled from the spot after locking the godown, they added.