The helpline - 0124-2301559 - was launched by Gurgaon Police Commissioner Alok Mittal.
The manually-operated number will work around the clock all seven days of the week.
"We will make available another number if needed. It will depend upon the frequency and number of calls received," Mittal said.
Following an assault on two youths from Nagaland here on the night of Oct 15, Minister of State for Home Affairs Kiren Rijiju had met a group of students from the northeast and assured them all possible help.
Aloto Chishi alias Sukoy and Awana alias James from Nagaland, both call centre workers, were beaten up and assaulted by a group of people in Sikanderpur area near the Mehrauli border. Five people were arrested for attacking the duo.