His school essays expressed opinions on the achievements of the Zionist party and the policy of the British government, which then ruled Palestine.

", a phrase used in the Jewish liturgy]At age 15, Haviv joined the Irgun Zionist underground movement and received the nickname "Efraim."

On finishing high school, Haviv joined the Palmach, the elite fighting force of the Haganah as a condition for being allowed to study at university, as the Jewish Agency obliged all Jewish high school graduates to spend a year either working on a kibbutz or serving in the Palmach.

On October 10, 1945, he participated in a Palmach raid on the Atlit detainee camp to free Holocaust survivors being held by the British authorities as illegal immigrants.

The raid freed 208 inmates, among them Yaakov Weiss, who would go on to join the Irgun and eventually be hanged alongside Haviv.

Gradually, he spent more and more time on operations with the Combat Corps of the Irgun (the HaK, hayil kravi), and as a result ended his university studies.

On March 1, 1947, Haviv took part in an Irgun attack on a British officer's club in Goldschmidt House, which was in Jerusalem's Russian Compound.

Haviv provided covering fire with a Bren gun for an Irgun sapper team which tossed explosive charges into the Goldschmidt House, leveling the building.

During the retreat from Acre Prison, other Irgun members shouted at him that the operation was over, but Haviv felt he had to wait for a formal order from Salomon before withdrawing.

Haviv and four other men; Meir Nakar, Yaakov Weiss, Amnon Michaelov, and Nahman Zitterbaum, were left behind.

According to some sources, they managed to hold the British at bay until their ammunition ran out, while the prosecutor allegedly stated that Haviv claimed to be a Haganah observer when he was arrested.

Avshalom got up and asked one of the witnesses, a British soldier who was present during his detention: "Can you explain to me precisely what you meant when you said to me 'gas chambers are a game compared to what is expected for you in Israel'?"

In his affidavit, Haviv equated the Irish War of Independence and American Revolution to the Jewish underground struggle: "... if you were wise, British tyrants, and would learn from history, the example of Ireland and America would be enough to convince you that you ought to hurry out of our country which is enveloped in the flames of holy revolt, flames which are not extinguished but only flare up the more with every drop of blood shed by you or in the fight against you.

You are amazed: how it occurred that these Jews of whom we thought to be cowards, who were close to slaughter for generations, rose against our reign, fight against our armies and even nullify our orders, scorn death?...

Is it death that will be feared by the members of a people from whom millions died in one horror, without reason and without end; in our remembrance of our destroyed friends—our hearts abound with joy that we were not crushed like them, because in our lot fell the holy prerogative to fight for our land, to be on the land of our birth, to write a chapter of courage and to leave a testament, not of cowardice and slaughter, but rather of strength and a battle for freedom, for the coming generations... And even this you will certainly not understand, when I, a young Hebrew man, who stands before a five-fold threat of murder, raise up my heart and my God in heaven, and give praise and thanks on the right that let me suffer for my land and my people, and say will all my existence: Blessed art thou, Lord our God, King of the Universe, who has granted us life, sustained us, and enabled us to reach this season!

In unison, the indicted parties sat bound and sang songs from the Betar Revisionist Zionist youth movement, which were translated for the many foreign journalists in attendance.

Consultation over the verdict lasted for nearly two hours during which time observers and journalists were transferred by the police to a grated porch under the sun.

After two hours, the presiding judge entered the hall wearing a red hat, a sign that the verdict was death.

According to the newspaper Davar, which carried out investigations in Haviv's household, his family had held on to the hope that he would be saved through a visit by the UN council.

This was in light of the UN calling on all sides to refrain from violence during the investigation, and also based on a similar event that had occurred in Greece along with the fact that no one from the security forces lost their life in the attack on the Acre Prison – the only victims were underground fighters.

A hostile government request for a conference concerning the three convicts worsened relations between the parties, and shortened the duration of the UN Council's stay.

When the prisoners' rabbi Aryeh Levin visited them they received him happily and asked him to report that they were in strong condition.

"Michaelov says that later that night the doors of the corridor opened and the hangman approached the convicts' cell together with some policemen, a military doctor and the manager of the prison in Nablus.

Twenty minutes later his body was brought out, and at 04:25 Yaakov Weiss ascended the gallows, where he too sang the "Hatikvah" with other prisoners joining in.

On the following day, July 30, at 10:00, the funeral cortege of the three fighters proceeded towards the graveyard in Safed Old Jewish Cemetery in a convoy led by a military vehicle followed by a family car and the "chevra kadisha".

This operation shocked Britain, despite the explicit threat beforehand, and brought to an end hanging of Jews in the British Mandate of Palestine.