A former Shin Bet security service coordinator who is being publicly identified only as "G." and earned the nickname "Captain Loai" in the Shin Bet, was a handler of Palestinian agents in the territories for almost eight years. Yesterday he spoke to Haaretz by phone from California from the apartment of none other than the man who was one of his most brilliant agents, Mosab Yousef, or the "Green Prince," as he was known. Yousef is the son of Hassan Yousef, once considered the head of Hamas in the West Bank.

Almost inconceivably, Mosab Yousef and G. became true friends after G. left the Shin Bet. The amazing story of the friendship between the agent and the handler, whose father is a reserve brigadier general in the Israel Defense Forces, will appear in full in tomorrow's Haaretz Magazine. In advance of the publication of the story, Captain Loai, 39, and a resident of the center of the country, who is married with two children, paid a visit to his friend Mosab in the United States.

The saga of Mosab Yousef, the Green Prince, was published about three months ago in Haaretz in advance of the release in the United States of his book (written with Ron Brackin ), "Son of Hamas." It is the story of the transformation of the oldest son of Sheikh Yousef into one of the Shin Bet's most important agents within Hamas. Throughout the book, the figure of Captain Loai features as Mossab's dominant handler and confidant.

In 2005, following Captain Loai's entanglement in a case involving the handling of funds, proceedings were initiated to have him dismissed from the Shin Bet and a year later he was officially out of the security service. In his Haaretz interview, G. says the only one who stood by him at the time and actually supported his version of events was Mosab Yousef. G. said his dismissal was related to efforts that he and Yousef made together to establish contact with a new intelligence source. "Something in my acquaintanceship with Mosab diverted me from the path I had chosen," he said.

G. hasn't been in the Shin Bet for four years, but says that something in him still seems to miss the days in which he hunted wanted suspects in Ramallah, and perhaps also the days and nights he spent with Yousef.

For almost seven years, Yousef had supplied G. with reliable information about what was happening within the Hamas leadership, including its plans to carry out suicide bombings or the location of wanted terrorists. Together the pair prevented dozens of terrorist attacks, including a plot to assassinate senior Israeli officials, including President Shimon Peres and former chief rabbi Ovadia Yosef.

The pair lost contact with each another, but G. learned of the whereabouts of the "Green Prince" when an article about him appeared in Haaretz in 2008. G. immediately re-established contact with Yousef in an e-mail in which he offered to help the "Green Prince." He concluded the e-mail: "Let your brother have the honor to help. Yours with love, G. (Luai )."