The accused, identified as one Naushad Jabbar Sidhiki, and the 20-year-old victim were studying at the same college in suburban Bandra and also were both residents of the Dharavi area here, said DCP (Detection) Dhananjay Kulkarni.
According to police, the accused had some time back told the girl that he possessed some objectionable photos of her and started blackmailing her into having physical relations with him, saying that otherwise he would post the photos on social networking sites.
The accused thereafter allegedly raped the girl on several occasions over the last six months. He is also alleged to have raped her earlier this month on the terrace of a private building opposite to their college, said Kulkarni.
Based on the complaint, Kherwadi police have arrested Sidhiki, the DCP said, adding that the accused was being questioned to ascertain whether he had committed similar offences with other girls.
The accused has been booked under Sections 376 (rape), 377, 323 (voluntarily causing hurt), 504, 506 (criminal intimidation) of IPC and Section 67 of the IT Act, police said.