The woman hired an autorickshaw to visit a relative's house near Kota late last evening but was gagged and taken to an isolated place by the driver and two of his friends present in the vehicle. She was raped by one of the three, a police official said.
As she raised an alarm, a person passing by the area on a motorbike came to her rescue. The culprits fled the scene, Vizianagaram Sub-Divisional police officer Ramana said.
On being alerted by the man, police arrived at the site and shifted the woman to a government hospital in Vizianagaram for medical examination. Her condition is now stable, he said.
A case under the SC and ST (Prevention of Atrocities) Act has also been registered against the accused since the woman belonged to the Scheduled Caste, police said.
The incident comes amid outrage over rape incidents in Kathua in Jammu and Kashmir and Unnao in Uttar Pradesh.