Police said almost 1200-1500 students have been questioned till now in connection with the incident that took place at Mukherjee Nagar in northwest Delhi on the night of December 31.
Two men in yellow and blue jackets tried to pull down a woman riding pillion on a motorbike near Batra Cinemas, investigators said.
Noticing the incident, police cautioned the two men, who appeared drunk, against indulging in hooliganism, the police said, adding CCTV footage shows the incident occurred between 11-11.15 PM.
"The two men fled after the police intervention. Police tried to explain to a few youths standing there that they should celebrate New Year but not at other's peril. They should not misbehave with women who are passing through the area," said a policeman who was present on the spot.
After the two men fled, a large group of students came and allegedly started pelting the policemen with stones, forcing them to take shelter in a police booth.
Mukherjee Nagar is a hub for students who prepare for competitive examinations like UPSC, banking and others, and it is suspected the two accused and those in the mob they later brought with them were students living in the area.
The policemen apprised the seniors of the matter and reinforcement was sent in to control the situation, sources said, adding the mob also vandalised police vehicles.
A case under relevant sections of the IPC for damaging public property, rioting, attacking a government servant and assault or criminal force to a woman with intent to outrage her modesty has been registered against unknown persons.
Section 354 (assault or criminal force to woman with intent to outrage her modesty) of the IPC was added on the basis of the statement given by constable Anil Kaushik, who was also an eyewitness and was injured during stone-pelting.
TV channels played the CCTV footage of the vandals running amok and indulging in stone pelting on policemen.
"Almost 1200-1500 students have been questioned till now to identify the students who were responsible for creating ruckus that day.
The SHO of Mukherjee Nagar has also formed a WhatsApp group with the owners of coaching centres to ascertain the identity of the hooligans," a source privy to the probe said.