In May 1949, after a wave of arrests, a group of Brothers made an unsuccessful attempt to assassinate prime minister 'Abd al-Hadi, leading to still more arrests. By July, some 4,000 Brothers were in prison, where they continued to maintain their organisation (Mitchell 1969, 80). Several trials followed; in one of these, Nuqrashi's assassin was condemned and put to death. The prosecution attempted to show that Banna had been responsible for the assassination, while the defence argued that he had been unable to maintain control over "extremists" in the secret apparatus; the court seems to have considered the latter view to be more plausible.