"Death to all three (Rahul, Ravi and Vinod)," Additional Sessions Judge Virender Bhat said.
After hearing the sentence, the three convicts pleaded for mercy but the court did not pay any attention, saying the case falls in the category of rarest of rare.
The Delhi Police had earlier sought death penalty for convicts -- Rahul (27), Ravi (23) and Vinod (23) while the defence counsel had sought leniency for them, saying there was chance of their reformation.
Holding that the girl was killed in a cold blooded manner, the court had on February 13 held the trio guilty of abduction, gangrape and murder and said they "gratified their sexual lust upon the deceased by subjecting her to rape one by one".
The three youths were arrested and booked for offences of kidnapping, unnatural sex, gangrape and murder of a girl on intervening night of February 9 and 10, 2012.
The court, however, had acquitted them of the charges of unnatural sex saying no such evidence was found against them.
According to the prosecution, the girl, who was working in Gurgaon's CyberCity, was abducted by the three in a car near her house in Qutub Vihar here and was gangraped and murdered by them on February 9, 2012.
Additional Public Prosecutor Satwinder Kaur had told the court that the victim's mutilated body was found three days after the incident from a field in Rodhai village in Haryana's Rewari district.
She had said the three youths had poured acid into the victim's eyes and had inserted a broken liquor bottle into her private parts.
Ravi and Rahul, who were residing in that area as tenants, were brothers and had planned to take revenge on the girl as she had rejected Ravi's advances.
The girl was kidnapped by the three youths when she along with three colleagues was coming back from her Gurgaon office, the prosecutor had said, adding they had dragged her into their car and had sped away.
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