According to the Delhi Police, the man named Deepak was found hanging from the ceiling inside the jail, where he was lodged.
The police rushed the victim to GTB Hospital but was declared brought dead by the hospital authorities.
The man was arrested yesterday for harassing a minor near his residence and was booked under the Protection of Children from Sexual Offences (POCSO) Act 2012.
He also had four pending cases on harassing in 2017 and was on the run, before his arrest.
The family members of Deepak, however, have alleged that he was being dragged into this case as a victim of the plot and did not commit suicide. They have demanded a fair investigation into the matter.
An enquiry has been initiated by the Metropolitan Magistrate.