Militants have launched a bomb and gun attack on a mosque in Egypt’s North Sinai province, killing 235 people, state media say.
The al-Rawda mosque in the town of Bir al-Abed was targeted during Friday prayers.
It is the deadliest attack of its kind since an Islamist insurgency in the peninsula was stepped up in 2013.
Egyptian President Abdul Fattah al-Sisi vowed to respond with “brute force” after talks with security officials.
No group has yet claimed the attack, but militants affiliated with so-called Islamic State (IS) have been responsible for scores of deadly attacks in the province.
They usually target security forces and Christian churches, and the bloody attack on a mosque associated with Sufi Muslims has shocked Egypt.
Witnesses said dozens of gunmen arrived in off-road vehicles and bombed the packed mosque before opening fire on worshippers as they tried to flee.
The assailants are reported to have set parked vehicles on fire in the vicinity to block off access to the mosque.
Pictures from the scene show rows of bloodied victims inside the mosque. At least 100 people were wounded, reports say, overwhelming hospitals.
“They were shooting at people as they left the mosque,” a local resident who had relatives there told Reuters news agency. “They were shooting at the ambulances too.”
Who was targeted?
Locals are quoted as saying that followers of Sufism, a mystical branch of Sunni Islam, regularly gathered at the mosque.
Although Sufis are widely accepted across much of the Muslim world, some jihadist groups, including IS, see them as heretics.
Who are Egypt’s militant groups?
What is Sufism?
The head of IS’s religious police in Sinai said last December that Sufis who did not “repent” would be killed, after the group beheaded two elderly men reported to be Sufi clerics.
Who might be behind the attack?
Militant Islamists have been waging an insurgency on the Sinai peninsula in recent years, stepping up attacks after Egypt’s military overthrew Islamist President Mohammed Morsi after mass anti-government protests in July 2013.
Hundreds of police, soldiers and civilians have been killed since then, mostly in attacks carried out by Sinai Province group, which is affiliated to IS.
In September, at least 18 policemen were killed when the group attacked a convoy near al-Arish.
Sinai Province has also carried out deadly attacks against Egypt’s Coptic Christian minority elsewhere in the country, and said it bombed a Russian plane carrying tourists in Sinai in 2015, killing 224 people on board.
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Sinai plane crash: What we know
The IS affiliate in Sinai
It has been operating mainly in North Sinai, which has been under a state of emergency since October 2014, when 33 security personnel were killed in an attack claimed by the group.
Sinai Province is thought to want to take control of the Sinai Peninsula in order to turn it into an Islamist province run by IS.