Background
Following this incident, the ISA began conducting a controlled operation in which the immigrant – who was given the code name Rasko – was operated as a double agent vis à vis the Romanian Intelligence (the Securitate). The operation lasted many years and was defined as "the Eastern European School for Intelligence" since the stream of information taught the ISA about Eastern European Intelligence and its modus operandi.

Introduction 
Rasko embraced both Zionism and Communism, and was a member in the Communist party since adolescence. During World War II he joined the Soviet forces fighting in the east; and at the end of the war returned to his hometown and launched an academic career.
His wife was also a scholar and a member in the Communist party since adolescence. She acknowledged the fact that she had been a recruit and a facilitator of the Securitate at their hometown. Her handling focused on providing reports about official visitors from abroad and the academic circle at her town.
When still living and training in Romania, before their deployment in Israel, the couple decided to cooperate with the Israeli security authorities and report about the espionage mission for Romania on their arrival.
Recruitment and training in Romania

The first task of the ISA was to interview the couple and learn all about their mission in Israel.
It took quite a bit of time and numerous meetings to study the information that Rasko furnished ─ general and specific information regarding his long term training in Romania before immigrating to Israel,  acquaintances, links to Romanian Intelligence officers, missions, and his evaluation of other agents operating in Israel.
Rasko's wife also passed a series of interviews which focused on the task she was given by the Romanian Intelligence: a radio operator for her husband and other Romanian agents operating in Israel.

In the course of their interviews, the couple disclosed they were recruited two years earlier, in the summer of 1956. Their recruitment was marked by several meetings with senior members in the Communist party and representatives in the Romanian Ministry of the Interior. The couple was told they were chosen to represent their country in an Intelligence mission in Israel and another Western country. Moreover, they were specifically told the decision to execute the mission is not up to them.

Rasko received a military rank on behalf of the Romanian Intelligence, an established tradition among Soviet Intelligence organizations. In the course of the two years prior to their deployment to Israel, Rasko and his wife were trained according to basic principles in several domains:
a. Principles of clandestine activity – detecting and shaking off surveillance, recruiting agents, methods of clandestine communication etc.
b. Knowledge of Western Intelligence organizations and their modus operandi.
c. Strengthening and implanting Communism (indoctrination) and reinforcing the bondage to their homeland Romania.
d. Land of Israel Studies in diverse areas such as economics, politics, and history.

At the end of the training, Rasko received a list of operational and Intelligence collecting missions to be carried out in Israel. He was instructed to find a job as a journalist, join a Zionist party, establish and cement extensive social ties, and collect information on political, military, and security issues.

Operating Rasko as a double agent
It seems that the Romanian Intelligence expected greatly from Rasko and considered him a valuable spy seeing the quality of the missions he was assigned. Therefore, the ISA was interested in turning Rasko into a double agent vis à vis the Romanian Intelligence; however, the couple faced a dilemma whether to agree to ISA's request to be double agents for fear of exposure by the Securitate and its ability to revenge.
Only after continuous spiels did Rasko agree to take part in the operation and become a double agent. Since then, all of Rasko's activities vis à vis the Romanian Intelligence were monitored by the ISA.

In the course of the long term operation, the ISA exposed Romanian Intelligence officers who maintained contacts with Rasko in Israel and abroad. Some were Intelligence officers working in Israel under cover as diplomats; some were officers who personally met Rasko abroad, and others arrived especially from Romania to meet him (the fact that the Securitate thought it right to risk and send to Israel senior Intelligence officers to meet Rasko suggests they valued him greatly).

Throughout the operation, various technological and communication means used by the Eastern European Intelligence were revealed. These included: cryptograph, encrypted messages, Dead Drops  dispersed in Israel. In addition, Rasko's handling by the ISA exposed Romanian and Eastern European Intelligence interests (through Rasko's Intelligence collecting missions), cover addresses used by the Romanian Intelligence, and its modus operandi.

The information accumulated in this operation was of considerable assistance to ISA's ability to foil the ongoing efforts made by Eastern European Intelligence agencies to send and recruit agents to Israel.

Epilogue 
Seven or eight years after the operation began, first questions were raised whether to end the operation and the link between Rasko and the Romanian Intelligence, since Rasko's handlers in Romania assigned him more and more complex missions that could not be fulfilled.

In 1965, the media published a story about an arrest of a Romanian Intelligence agent operating in Israel (see the E.S. Case). Rasko informed the Romanian handlers about his intentions to end the operation with Romania for fear of being exposed. The Romanian Intelligence refused and his handlers tried to convince him to continue and work for them while clarifying that it is not up to him to decide. But to no avail…

The ISA considers the handling of Rasko as one of the most important and valuable operations in the area of thwarting Eastern European espionage, and Rasko as ISA's best teacher in the field of Eastern European Intelligence field work.
The operation with Rasko and his lengthy handling vis à vis the Romanian Intelligence were considered as one of ISA's best achievements, and ironically the Romanian Intelligence also considered Rasko a great success.