The Israel Defense Forces said it had confirmed the assassination of Hamas military chief Izz al-Din al-Haddad in Gaza on May 16, and Hamas also confirmed his death, The Times of Israel reported on May 18. Meanwhile, Israel's Prime Minister Benjamin Netanyahu admitted on May 17 that Israel had been expanding its control of Gaza beyond the "yellow line" of control agreed to during the October 2025 ceasefire.

On May 18, Israel's navy began intercepting a new aid flotilla headed for Gaza off the coast of Cyprus, the latest humanitarian attempt to break through Israel's blockade. Recurrent humanitarian flotillas have unsuccessfully attempted to break through Israel's blockade since the 2023 war began, with no fatalities so far, as the Israeli navy changed tactics to avoid a repeat of the 2010 flotilla scandal that killed nine people and led to severe international condemnation.