Suresh, a handloom worker from the district, was arrested for allegedly uploading the morphed pictures of the woman, Salem SP, Amit Kumar Singh said.
The accused has confessed to his crime. He said that he did so because she had turned down his marriage proposal, Singh told reporters.
A Vinupriya, a Chemistry graduate, had committed suicide by hanging herself in her house in Salem on Monday after a morphed picture showing her in an obscene fashion, was uploaded on Facebook by unidentified persons.
Meanwhile, a policeman who had demanded and got a mobile phone as bribe from Vinupriya's father has been placed under suspension.
Cyber crime constable Suresh Kumar has been placed under suspension for getting the mobile phone to investigate the case, police said.