The minor was found lying at an open ground after the sexual assault this morning, police said.
Later, an 18-year-old youth was arrested by the police on the basis of a CCTV footage of the area.
The victim, who stayed with her mother in a slum colony, had left her house in the morning, police said adding, following the incident, she was admitted to a government hospital and was reported to be out of danger.
"The accused, a student of class XII at a nearby college, was caught on the basis of the footage of CCTV camera, which was installed by a person outside his place for safety purpose," Deputy Commissioner of Police Manoj Patil told reporters.
"We could easily identify the accused with the help of the footage and during the interrogation, he confessed to the crime," Patil said.