Indirapuram police station in charge Haridayal Singh Yadav said that Raju (23), a peon in a coaching institute, barged into the victim's room when she was alone, and raped her at knifepoint last evening.
After committing the crime, Raju fled the scene, he said, adding that later he was arrested from Delhi yesterday.
The father of the victim is a security guard and staying with his family in a rented accommodation at the rooftop. Raju was also living in another room on the same roof top, he said.