[3] After the Korean war broke out in 1950 he was appointed Chief of Staff, replacing Kang Kon who had been killed in action.

[3] When the Korean War reached a stalemate in July 1951, Nam served as the Communists' chief delegate at the armistice talks.

[3] Nam, along with Pang Hak-se (the founder of the DPRK secret police), was one of only a few prominent Soviet Koreans who survived the purges of the 1950s.

Many suspected that this was not an accident, and some blamed Kim Jong Il, who by that time was not powerful enough to simply order that Nam be killed.

[3][7] Nam Il's son, who lived in the Soviet Union, visited North Korea and attempted to investigate, but Pang Hak-se told him to go home and stop interfering in affairs which did not concern him.