Mustafa Jumaah was killed by a sniper in the city of Sheikh Zuweid, the Palestinian Ma'an News Agency reported.
Security forces carried out an aerial search for the shooter, while troops on the ground raided suspected militant strongholds near Rafah and Sheikh Zuweid.
It was not reported whether the sniper was found.
Also Saturday, Egyptian forces in El-Arish detained 28 suspected fugitives, as well as a number of Palestinians who had entered Egypt through Gaza's smuggling tunnels, officials said.
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