The victim, who pursues the course in Uttarakhand and is in the capital for her internship, is in a "critical condition" at the Safdarjung Hospital where she was rushed late last night after the crime which sparked outrage.
Both the girl and her male friend, who had boarded the chartered bus with tinted glass windows from Munirka in south Delhi around 9.45pm to Palam, were assaulted with an iron rod by the men after the duo resisted before they were dumped on the road side near Mahipalpur flyover, police said today.
Chief minister Sheila Dikshit said government would take all necessary steps to ensure that such incidents do not recur.
"I have been told by transport department that their licence has been cancelled. We will take all the necessary measures to ensure that such incidents don't happen," she said.
Delhi Transport department had planned to install CCTV cameras in all its buses long back but it is yet to be implemented.
Asked whether government was also planning to make it mandatory for installing CCTV cameras in private buses, an official in the Women and Child Welfare department said government was considering it.