Born December 25, 1924 in Jerusalem, as Yosef Danoch. After the establishment of the State of Israel changed his name to Avni (his underground cover name). Went out to work as a locksmith at a young age, to help provide for his family (learned his job at his cousins' workshop, the Sabah brothers).

At 16 joined Betar and four years later (in 1942) joined the Irgun.

After the declaration of the Revolt (February 1944) became part of the fighting force, and on top of being in charge of arms dump in Jerusalem took part in many operations.

In the second attack on the British Intelligence offices in the Russian Compound (December 27, 1945) he was charge on the sappers unit. He also took part in the attack on the King David Hotel and the Schneller Army Camp.

Was arrested in 1947 and detained by the British in Latrun Camp. Was released on March 1948 and took part in the conquest of Deir Yassin, where he was wounded upon attacking the Muchtar's house.