Egyptian state media says more than 230 people have been killed after militants attacked a mosque in North Sinai with a bomb and guns.
Reuters says 235 people were killed the November 24 attack on the mosque in the town of Bir al-Abd, some 40 kilometers from the provincial capital, El-Arish, and that the government had declared three days of mourning.
State television reported that Egyptian President Abdel Fattah al-Sisi had convened an emergency security meeting shortly after the attack, which left dozens of others injured.
The militant targeted a mosque frequented by security forces and and members of the Sufi sect. The Islamic State group considers Sufis heretics because of their less orthodox interpretation of Islam.
No one has claimed responsibility yet, but the IS affiliate in Sinai has targeted Sufis several times before.
The Associated Press quoted three police officers as saying that assailants in four off-road vehicles fired on worshipers inside the mosque during weekly Friday Prayers.
Reuters quotes resident Ashraf el-Hefny who said many of the victims were workers at a nearby salt firm who had come for Friday services at the mosque, which had contained some 300 worshipers.
Egyptian authorities have been battling Islamic State militants in the northern Sinai Peninsula.