The incident cleared for publication this week, in which the Shin Bet (Israel Security Agency) arrested alleged Iranian intelligence agent Ali Mansouri in Israel differs from previous cases which have occurred in the last decade.This time, it appears that the recruitment and running of the agent was carried out by the Iranian Revolutionary Guard's special operations unit (Quds Force), rather than by the Iranian intelligence agency. Among other things, the role of the Quds Force is to execute terror attacks against Israel and additional targets in the West and in the Middle East. The significance of this is that Mansouri was not sent to Israel to spy and collect intelligence like his predecessors, but rather to establish an infrastructure to carry out terror attacks within Israel.It warrants noting that the Revolutionary Guard's Quds Force was behind the February 2012 terror attack in which an employee of the Israeli embassy in Delhi was wounded, and was also responsible for attempted terror attacks in Bangkok and Tblisi, Georgia, as well as previous plots in Azerbaijan, Kenya and Nigeria.An additional important fact, which displays a new pattern in Iran's strategy against Israel, is that the process was completely compartmentalized from Iran's general intelligence establishment, and it was reminiscent of Western intelligence operations.The Iranians identified Mansouri based on his characteristics and skills, which included Iranian origins, Belgian citizenship and a worldwide business background. The recruitment of Mansouri was a prolonged process, and he was provided with an intricate cover story with all of his movements and actions effectively disguised. These measures were taken in order to hide the fact that he had repeatedly entered and left Iran, and that he had Iranian citizenship.Mansouri was arrested during his third visit to Israel, however, that does not necessarily mean that he was not discovered beforehand. The eternal dillema of preventative intelligence is deciding at what stage to arrest a suspect in order to best serve the ultimate interest: collecting the maximum amount of information about the agent and his actions, particularly in regard to his connections with additional operatives.The arrest of Mansouri while he was attempting to depart Israel at Ben-Gurion Airport was not random, nor was it solely the result of the airport autorities' security procedures. The Shin Bet uses many tools to identify suspicious patterns of activity, including information provided by foreign intelligence sevices, intercepted signals, monitoring of computer communications, detection and identification of suspicious activity, tips from the public, and a suspect profile.The methods employed by the Iranians in the Mansouri case, which differ from Tehran's previous operations, require Israel's intelligence establishment to adjust accordingly. Intelligence officials must now understand that the Iranians have shown themselves to be a sophisticated, patient and calculating adversary that acts and plans for the long-term. Nevertheless, the Iranians likely made a number of errors in running the agent which led to his being discovered, arrested and prevented from carrying out his mission. The Iranian operation was patterned after Western intelligence methods which are very familiar to the the Shin Bet and Mossad.During the 1990s, and in the last decade, quite a few European passport holders sent to Israel as tourists by Hezbollah and Iran were arrested. Many Israelis, both Jews and Arabs, were detained and questioned after being pressured by Iranians, usually while trying to organize trips to visit family in Iran at Iran's embassies in Turkey and in other nations.The most recent Iranian attempt failed, like most of their previous efforts. Most of the previous recruitments were carried out in Iranian embassies or in Iran, sometimes in a violent and blunt fashion. However, it turns out that in this instance as well, despite the great caution and strict compartmentalization, the Shin Bet succeeded in discovering the agent and thwarting his actions. It bears reminding that the Iranians also use Hezbollah as an additional long arm for collecting intelligence and kidnapping Israelis (such as Elhanan Tenenbaum). In this area as well, Israel has succeeded in stopping most of the plots.Identifying this kind of undercover, secret agent is not easy. The foreign citizenship, the business cover and the personal background make it difficult to uncover suspects. It is probable that Iran, as well as other countries, will continue trying to send spies to Israel in order to collect high-value intelligence information, either for civilian or military purposes. The Shin Bet's real challenge is to identify suspicious signs, patterns and activities suggestive of espionage or terror, collect intelligence and use it properly in order to both prevent the activities themselves and glean information for thwarting future plots.The writer is a former brigadier-general who served as a division head in the Shin Bet (Israel Security Agency).