Adhikari had died at the ICU of Bir Hospital on September 23 last year while staging fast-unto-death demanding that the Maoists involved in killing his younger son Krishna Prasad Adhikari's murder during the period of armed conflict be punished.
The NHRC has been urging the government to take legal action against the murderers of Krishna Prasad and provide reparation to the family since last eight years.
Nanda Prasad's wife Ganga Maya has continued the struggle for justice from her bed at the Bir Hospital.
"I know who murdered my son but they are roaming free. I'll continue my struggle for justice," said Ganga Maya on Wednesday at a press conference at the hospital.
Krishna Prasad, 18, of Phujel, Gorkha was abducted and murdered by the Maoists during the insurgency in 2004.
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