The ISA first tracked him down in February 1962 after the censorship intercepted a letter destined to an address in Rome known to serve the Egyptian Intelligence. The letter which was written in English did not provide many details since the name or the address of the sender were not included. The content indicated that the writer arrived to Israel on December 24, 1961, and was staying at a Kibbutz.

The first attempts to trace the suspect were unsuccessful. However, the censorship's continuous monitoring lead the way to additional letters sent to Rome, and a letter sent from an address in Rome to a man named Zaki Salim who was living in the Kibbutz of Negba, located in southern Israel. A lab test of this letter suggested it contained secret writing in Arabic.

In February 1962, Zaki (Ben Salim) Kuchuk was traced and suspected to have conducted the clandestine interchange of letters in secret writing. His final identification was confirmed in October 1962 since he reported in one of his letters to Rome that he had moved to Ashkelon.

Following his trace, the ISA learned of Kuchuk's departure from the Kibbutz where he learnt Hebrew, to an apartment in Ashkelon provided by the Jewish Agency, and his plan to join the IDF on November 5, 1962. The ISA enabled his recruitment to the IDF after coordinating with the IDF Field Security Office (nowadays called the Information Security Department), but Kuchuk was limited from the start to non sensitive and classified roles only and was closely monitored. He was placed as a driver at the Home Front Command HQ.

He served at the IDF for only one year and received an early release in November 1963 under a pretence that he is over aged and wishes to start a family. On December 19, 1963, Kuchuk was arrested at his apartment in Ashkelon. One of the reasons for his arrest was his intention to marry an Israeli woman who was unaware of his true identity.

Recruitment to the Egyptian Intelligence
Zaki (Ben Salim) Kuchuk was actually Kaborak Yaacobian, an Armenian, born in 1938, in Cairo, whose parents had fled the massacre of the Armenians in Turkey.

Yaacobian lacked citizenship and worked as a photographer at a photo printing shop in Cairo. In 1959, Yaacobian and his friend were arrested by the Egyptian police for keeping company with prostitutes. He refused to testify against the prostitutes; therefore, he was sentenced to a one and a half year of imprisonment for running a brothel.

In January 1960, at the time of his imprisonment, a rumor spread in prison that the authorities were searching for speakers of foreign languages. He filed his candidacy and was interviewed in prison by an Intelligence Egyptian officer who tried to recruit him to an Intelligence mission abroad. At some point, Yaacobian understood that the mission will take place in Israel, and he refused.

Yaacobian was released from prison after appealing to reduce his sentence. Shortly after the release, Yaacobian encountered financial problems since his criminal record made it hard for him to find a job. At this point, the Intelligence officer renewed contact with Yaacobian and tried to convince him to join the Egyptian Intelligence service for a three year period and promised to issue him an Egyptian citizenship, provide economic welfare for his widowed mother, and discharge him from Egyptian military service. This time Yaacobian accepted the offer.

The process of his recruitment consisted of Intelligence guiding, a new identity of a Jew given by the Egyptian Intelligence, and even circumcision. His new identity was of a Thessaloniki born Jew who immigrated to Egypt with his mother. Yaacobian was given two photos by the Egyptian Intelligence – a photo of the Jewish cemetery in Cairo and a photo of his (false) mother's grave. One of his handlers accompanied him to the central Jewish synagogue in Cairo several times, mostly on Saturdays and Jewish holidays so he could learn about Judaism and Jewish customs. This preparation was quite superficial and in fact, he was completely ignorant regarding Jewish tradition and customs.

After being given a laissez-passer by the name of Yizthak Kuchuk, Yaacobian was instructed to arrive to the Red Cross office and ask for assistance to immigrate from Egypt. He was told to turn to the UNHCR (United Nations High Commissioner for Refugees); there he was offered two destinations – one of them was Brazil and that was his choice. When arriving to the Brazilian Consulate, Yaacobian presented the necessary documents, including a document from the rabbinate in Cairo confirming his identity as Yitzhak Kuchuk. This document was of course provided by the Egyptian Intelligence.

Immigration to Israel
Yaacobian arrived to Brazil on April 26, 1961, on a boat leaving from Italy. On his way he made friends with an Israeli family from Kibbutz Bror Hayil on its way for a family visit in Brazil.

One of his Egyptian handlers was specifically deployed to Brazil in order to direct the operation and he instructed Yaacobian to strengthen his ties with the Israeli family. Infiltrating into Israel was quite an easy task for Yaacobian: the father of the family convinced him to immigrate to Israel and even arranged a meeting between Yaacobian and relevant representatives from Zionist institutions within Brazil responsible for immigration. Soon Kuchuk / Yaacobian received an immigration visa and even signed a written commitment to serve in the IDF.

Close to the time of his "immigration" to Israel, Yaacobian's handler equipped him with money and cameras. On his way to Israel, Yaacobian met with his Egyptian recruiter who gave him one last briefing in Genova, Italy. At the first part of his handling, the Egyptians wanted to see Yaacobian's acclimatization and the standing of his cover story in Israel. According to the Egyptian plan, he was instructed to find a job in a photo printing shop in the area of Tel Aviv and after eight months of acclimatization, attempt to depart to Egypt through Cypress; there, his handlers would consider whether to invest in his own photo printing shop in Tel Aviv. He was told that during the visit in Egypt they plan to teach him clandestine radio communication and equip him with a radio device that will be handed to him in Tel Aviv.

The Egyptian Intelligence and Yaacobian set up clandestine means of communications using cover addresses in Italy (Rome). He was instructed and equipped with materials for secret writing and equipment to develop it. As for his hostile Intelligence reconnaissance task, during the stage of his acclimatization Yaacobian was directed to report about signs of alertness or abnormal situation in Israel.

Kuchuk / Yaacobian arrived to Israel on December 24, 1961 but the course of things did not go as planned. He was sent according to his request to an Ulpan (an intensive Hebrew course) at a Kibbutz and in November 1962 he was recruited to the IDF. His Egyptian handlers instructed him to try and serve at the armored corps but he failed to reach a significant role in IDF since the ISA and the Information Security Department foiled his attempts. His other requests included doing a regular service at the IDF and working as a photographer at the Intelligence branch in the Central Command HQ (he claimed that he was offered this job by one of his commanders), but these requests were rejected for the obvious reasons. In May 1963, he filed candidacy for officer candidate expediency tests, but failed them. In November 1963 he was released from IDF and shortly afterwards arrested.

Information delivered to the Egyptians
Kuchuk / Yaacobian disclosed in his interrogation that up to his arrest he dispatched 18 letters, 6 airmail letters, and 2 postcards to his handlers. He received 8 letters and 3 postcards. He managed to report to his handlers some critical information:

• Location of armored corps base at Julis and the existing number of tanks.
• Location of Chasa camp, near Julis.
• Location of Home Front Command HQ in Jaffa.
• Expected procurement of Mirage jets, tanks, and other modern weaponry.
• Mirage, Dassault Mystère and Ouragan training flights in the area of Lakhish.
• Location of an existing nuclear facility between Dimona and Sodom.
  

Epilogue
Yaacobian was put on trial for espionage and in March 1964 he was sentenced for 18 years of imprisonment. Two years later, in March 1966, he was released in an Israeli-Egyptian prisoners exchange agreement. Yaacobian and 2 other Egyptians were transferred to Egypt in exchange for 3 Israelis who mistakenly crossed the border to the Gaza Strip.