Sketches of the other two accused were expected to be released soon, Udupi SP Dr Boralinagaiah told reporters.
IGP (Western Range) Pratap Reddy said the police have lodged an FIR under sections 363 (kidnapping) and 376 D (sexual assault by gang) against unknown persons.
Police are confident of nabbing the accused as they are working on leads secured on the suspects and the auto used for committing the crime, Reddy said.
"We have questioned 15 to 16 people, he added.
Reddy said the police have formed 11 teams and 200 officials are working on the case.
The IGP said the victim, who suffered a fracture in her legs and injuries on her hands and neck, was stable and out of danger and added that she was being constantly being counselled by doctors.
Reddy said the police could not interact with the girl directly and it was done through the doctors and medical attendants, and hence the process was delayed.
For the same reason, the investigation too was not moving as fast as expected, he added.
The police were waiting for the girl to recover before questioning her directly, he said.