About an hour after the shooting, Shin Bet (Israel's internal security service) opened an investigation, focusing its efforts on the Lehi veterans group led by Menkes and Heruti. The group had been linked to various murder incidents and various actions against Kasztner, and it was suspected that Menkes bore personal responsibility. In addition, Kasztner delivered a description of the assassins at the hospital. After a lengthy investigation, Shin Bet identified Eckstein, Shemer and Menkes as the assassins. Shemer was the first to confess his role, and implicated Eckstein, who subsequently confessed and implicated Menkes. In addition, police tracked down the jeep used by the assassins, which was found to contain the murder weapon and fingerprints belonging to Shemer. Subsequently, twenty members of their organization were arrested, including Heruti, and two weapons caches belonging to the group were discovered.