 He gave Israel enough information to secure their trust and thus was able to mislead Israel regarding the timing of Egypt's attack in the 1973 Yom Kippur War.From 1969, Marwan served in the Presidential Office, first under Gamal Abdel Nasser and, then as a close aide to his successor, President Anwar Sadat.In 2002 it became known that, during the period leading up to the October 1973 Yom Kippur War, Marwan spied for Israel (under the Mossad code-name "The Angel").