Release pleas of model Jessica Lal and law student Priyadarshini Mattoo's killers were rejected by the Delhi Sentence Review Board on Friday, sources said.
Manu Sharma, the convict in the murder case of Jessica, and Mattoo's killer Santosh Singh were among 204 who had approached the board, headed by state Home Minister Satyendar Jain, the sources said.
The board approved release requests of 59 convicts and rejected 145 such pleas, they said.
Jessica was shot dead by Sharma after she had refused to serve him liquor at the Tamarind Court restaurant owned by socialite Bina Ramani at Qutub Colonnade in south Delhi's Mehrauli area on the night of April 30, 1999.
Sharma has been in jail for years now and had earlier approached the Delhi high court after the board in October had rejected his plea for release.
The high court had in January directed the Aam Aadmi Party government to consider Sharma's request for premature release.
Sharma, son of former Union minister Venod Sharma, was sentenced to life imprisonment by the high court in December, 2006.
The trial court had acquitted him earlier, but the Delhi high court had reversed the order and the Supreme Court had upheld his life sentence in April, 2010.
On the other side, Santosh Singh is serving life term for rape and murder of Delhi University student Mattoo, 25, in January 1996.
Singh, also a law student at Delhi University, was acquitted by the trial court in the case on December 3, 1999, but the Delhi high court had on October 27, 2006 reversed the decision, holding him guilty of rape and murder and giving him death penalty.
Singh, son of a former IPS officer, had challenged his conviction and death sentence given by the high court.
In October 2010, the Supreme Court had upheld Singh's conviction, but reduced the death sentence to life imprisonment.
The Sentence Review Board has the prisons director-general, home secretary, state law secretary, a district judge and the government's chief probationary officer and a joint-rank officer of Delhi Police as its other members.