According to the police, all 12 were arrested on Thursday after a major manhunt following a complaint of the victim.
She was returning to the university on a scooty with her friend on Tuesday evening when they were stopped near the Sangrampur brick kiln factory by the youths travelling in a car and a bike.
As per the complaint, nine youths stopped the victim along with her friend. The victim was forcibly taken into the car and her friend was held at gun point. After abduction she was taken to a secluded place where three more youths were called to join the gang.
She was allegedly gang raped and then left on spot.
The victim lodged compliant to police on Wednesday. One of the accused's mobile was found at the crime spot which led to the arrest of all 12 on Thursday.
The police have recovered the car and bike. One country-made pistol and some live cartridges were also recovered from the arrested youths. All have been sent to jail.
The law student's medical test has been conducted.
The police did not mention anything about the gang rape initially. But, later revealed the information after arresting the youths.
The case has also been registered under the SC Act as the girl belongs to the tribal community. The police has said that a speedy trial will be sought to ensure justice to victim.
( With inputs from IANS )