A 46-year-old married man allegedly committed suicide at his residence in northeast Delhi's Nand Nagri on Wednesday, police said.
The deceased was identified as Hari Shankar, who worked as a labourer, they added.
Police was informed about the incident at 4 pm by his 22-year-old son.
A suicide note was recovered from him in which he has not held anyone responsible for his death, police said.
During the investigation, police learnt the man was in a relationship with a 21-year-old woman and it is suspected that he was guilty about involving in an extramarital relationship.
(With inputs from agencies.)