The police action in Tel Aviv, codenamed Operation "Shark", began on 30 July and achieved several successes, including the discovery of a large weapons cache in the city's main synagogue, and the arrest of the LEHI's leader Yitzhak Shamir. But the most important figure of the Zionist underground, Menachem Begin of the Irgun, slipped through British hands. He hid in a secret compartment in his house while British soldiers stayed in his home for two days. General Barker later recalled: "We should have caught him, but the men did not search his house properly. This is one of the problems of search operations. You have to rely on very junior people, and, if they make a mistake, the whole operation can be damaged."