The five were convicted in the case on October 14, 2014.
Accused Shamshad alias Khutkan, Usman alias Kale, Shahid alias Chhota Billi, Iqbal alias Bada Billi and Kamruddin were tried for the kidnapping and gang rape of a 30-year-old call centre executive in Dhaula Kuan area of south Delhi.
According to police, the five men abducted the victim, who hailed from the northeast Nov 24, 2010, while she was walking home with a friend after her shift ended. The abductors took her to Mangolpuri, gang-raped her, and left her on an isolated road there.
The five were later arrested from Mewat in Haryana. They had claimed innocence, saying they were falsely implicated in the case.
After the incident, Delhi Police issued an order to all BPOs in Delhi and the National Capital Region to drop women employees home safely while providing them security.
(With agency inputs)