Yosef, son of Hayim and Zakia Yagen, who made aliyah in the year 1922 from Turkey, was born in Jerusalem on 2 February 1932. Already at a young age, the fire burned within him to fight foreign rule, and he joined the ranks of Lehi when he was fifteen. He operated as a member of the movement for about a year and a half, and according to this friends and family, “he was happy to join the fight out of deep recognition and faith.”

He was injured in the Tanus House operation, alongside the Old City, where the Arab gangs had their command post and which was captured by Lehi’s daring attack. Once he recovered, he set out for the joint attack by Lehi and IZL on the Der Yassin village in western Jerusalem.

In the morning of 9 April, 1948, at the launch of the attack, Yosef was hit in his mouth by a bullet and killed. The first Lehi base in Jerusalem not to be underground was named after him, Mahane Eldad. It was located in Lifta, in the western part of the city; this area was liberated by Lehi as well and served as the headquarters for the “Religious Department,” until Lehi was forced to disarm in Jerusalem after the assassination of Count Bernadotte.

Yosef was buried in Sanhedria, then interred in the Mt. Herzl Military Cemetery in Jerusalem on September 13, 1951.