One of the accused, Manoj Kumar, 22, allegedly tried to slit her throat with a blade, a police officer told IANS.
Pradeep Ram, 19, who was nabbed Monday from Bihar, told police that despite the girl bleeding heavily after being raped by Manoj, Pradeep also raped her.
Pradeep told police when the girl started crying they decided to kill her to hush up the crime.
"Seeing the girl bleeding and crying, they decided to kill her. Pradeep tried to strangulate her but he was inebriated and could not kill her. After that Manoj tried to slit her throat with a razor blade," police said yesterday.
Manoj and Pradeep will be brought face to face after police conduct a test identification parade of the former.
Pradeep told police that Manoj had come to his rented accommodation in Ghaziabad around 3 pm on April 15 where they ate chicken and consumed alcohol.
"They both returned to Manoj's house in Gandhi Nagar in east Delhi. On their way they again bought alcohol and consumed it at Manoj's room," said the police official.
The duo, who would watch porn clips on their mobile, then decided to call prostitutes.
"When Manoj went out of his rented accommodation, he saw the girl playing. He lured her and brought her to his room. Both of them raped her," said the officer.
After the attempt to slit her throat, Manoj locked the girl inside his house and along with Pradeep went to New Delhi Railway station.
They both boarded the train for Chhapra in Bihar where Manoj took Pradeep to his in-law's place in Muzaffarpur.
Pradeep went to his maternal uncle's place in Lakhisarai from where he was nabbed.
The girl was abducted and kept hostage for two days without food and water in the room in which the attackers lived on the ground floor of a building in east Delhi's Gandhi Nagar. The girl's family stays in the same building.
The girl was rescued when members of her family heard her screams April 17.