[5] His network, which among others included military officers John Hagle and Eivind Hjelle, developed into the clandestine organisation XU.

The name XU (X=unknown, U=undercover agent) was taken from an undercover group Sand had run in the Dutch East Indies during World War I.

[4] The same night Hagle and Helle were also hunted by the Germans, but managed to escape, fleeing to Sweden and later travelled to London.

[14] Sand was haunted by pains, stress, nightmares and hallucinations after the liberation, but worked for war veterans for the rest of his life.

[1] A bust of Sand, with the single word "Nei" (English: No), was revealed at Griniveien near Eiksmarka in 1952, with the presence of both King Haakon and Crown Prince Olav.

The word "Nei" was inscribed on the bust because this was the only answer Sand would give his interrogators during the four years of captivity and torture,[1] despite having "every bone in his body" systematically broken,[according to whom?]

Sand died, from the wounds he sustained during World War II captivity,[citation needed] on 17 December 1956 in Bærum.