With the start of the gang war, the Gallo crew retreated to the Dormitory. On June 6, 1962, Profaci died of liver cancer and Magliocco became the family boss. However, the Mafia Commission did not endorse him as the new family leader. Afraid that the other New York families viewed him as weak, Magliocco increased the tempo of violence against the Gallo faction. In turn, car bombs, drive-by shootings, and other murder attempts were made against Magliocco men such as Carmine Persico and his enforcer, Hugh McIntosh. In 1963, with the jailing of Gallo and several associates, the hostilities temporarily ended. In 1963, Joseph Bonanno, the head of the Bonanno crime family, made plans to assassinate several rivals on the Mafia Commission—bosses Tommy Lucchese, Carlo Gambino, and Stefano Magaddino, as well as Frank DeSimone. Bonanno sought Magliocco's support, and Magliocco readily agreed. Not only was he bitter from being denied a seat on the Commission, but Bonanno and Profaci had been close allies for over 30 years prior to Profaci's death. Bonanno's audacious goal was to take over the Commission and make Magliocco his right hand man. Magliocco was assigned the task of killing Lucchese and Gambino, and gave the contract to one of his top hit men, Joseph Colombo. However, the opportunistic Colombo revealed the plot to its targets. The other bosses quickly realized that Magliocco could not have planned this himself. Remembering how close Bonanno was with Magliocco (and before him, Profaci), as well as their close ties through marriages, the other bosses concluded Bonanno was the real mastermind. The Commission summoned Bonanno and Magliocco to explain themselves. Fearing for his life, Bonanno went into hiding in Montreal, leaving Magliocco to deal with the Commission. Badly shaken and in failing health, Magliocco confessed his role in the plot. The Commission spared Magliocco's life, but forced him to retire as Profaci family boss and pay a $50,000 fine. As a reward for turning on his boss, Colombo was awarded the Profaci family. On December 28, 1963, Joseph Magliocco died of a heart attack at Good Samaritan Hospital Medical Center in West Islip, New York.