"It is the first time that Nepal Army personnel have been convicted by a civilian court for crimes committed during the 1996-2006 conflict," Rupert Colville, a spokesperson for the Office of the UN High Commissioner for Human Rights (OHCHR) said.
"None of the officers were present in the District Court of Kavre, and it still remains to be seen whether they will actually be arrested and serve their sentences," he added, urging the country's authorities to implement the verdict on what he called an "extremely important emblematic case".
She was allegedly subjected to torture and later that month died in the custody of the army at the Birendra Peace Operations Training Centre in Panchkal, located about 15 kilometres from the village where she was arrested.
According to the OHCHR spokesperson, the Nepalese Army and the Government initially denied any knowledge of Sunuwar's fate or whereabouts and her body was buried secretly.
Colville added that OHCHR as well as other human rights organisations have persistently advocated for those responsible to be held fully accountable, and the convictions this Sunday come after a long succession of unsuccessful attempts to seek justice for the murder.