Militants tried to stop people from escaping from the area by blowing up cars and then using the burning wrecks to block roads.
At least 235 people have been killed and dozens more injured after a suspected Islamic State bomb and gun attack on a mosque in Egypt.
The country’s government has declared three days of mourning following the assault on al-Rawdah mosque – the deadliest ever attack on Egyptian civilians by Islamic extremists – which has also wounded around 130 people.
The mosque is in Bir al-Abed in the volatile northern Sinai Peninsula, around 25 miles from the provincial capital of el-Arish, which has been regularly targeted by IS militants in recent years.
No group has yet claimed responsibility for the attack – which came as worshippers took part in weekly Friday prayers – but state news agency MENA reports that it “appeared” to have been carried out by IS.
President Abdel Fattah al Sisi has called an emergency security meeting.
Officials said the militants arrived at the mosque – largely attended by Sufi Muslims, considered heretics by IS – in four off-road vehicles before storming the building and detonating a bomb and opening fire, with ambulances then seen taking casualties to nearby hospitals.
“They were shooting at people as they left the mosque,” said a local resident whose relatives were at the scene.
“They were shooting at the ambulances too.”
Another local resident, Ashraf el-Hefny, said many of the victims were workers at a nearby salt firm.
He added: “Local people brought the wounded to hospital on their own cars and trucks.”
Police officers said the militants had tried to stop people from escaping from the area by blowing up cars and then using the burning wrecks to block roads.
Cairo’s international airport promptly boosted security following the attack, with troops seen patrolling passenger halls, conducting searches and manning checkpoints.
Prime Minister Theresa May tweeted to say she was “appalled” by the “sickening attack”, with US President Donald Trump condemning it as “horrible and cowardly”.
Appalled by the sickening attack on a mosque in North Sinai. Condolences with all those in #Egypt affected by this evil and cowardly act.
— Theresa May (@theresa_may) November 24, 2017
Horrible and cowardly terrorist attack on innocent and defenseless worshipers in Egypt. The world cannot tolerate terrorism, we must defeat them militarily and discredit the extremist ideology that forms the basis of their existence!
— Donald J. Trump (@realDonaldTrump) November 24, 2017
IS militants have killed hundreds of police and soldiers in the region since fighting intensified over the last three years, although they have mostly targeted Egypt’s security forces.
They have also struck against Christian churches and pilgrims in the country and a bombing in October 2014 saw the Government declare a three-month state of emergency, but Friday’s attack is region’s the deadliest to date.
Middle East analyst Timothy Kaldas told Sky News that the military’s “scorched Earth” approach towards eliminating IS did not appear to be working and described the scale of the attacks in the region as “unprecedented”.
“The number of attacks has gone down slightly but the casualty figures have actually risen,” he said.
“Not enough has been done to win over the local population to deny Isis safe haven recruits. There’s been reports of abuse where captured militants have been executed by the military, so there’s a lot of concerns that the way the Government is approaching things is actually increasing militancy rather than decreasing it.”
The attack comes days after a deadly bombing on a mosque in Nigeria, which killed at least 50 people.