Militants killed more than 305 people at a mosque in North Sinai on Friday, detonating a bomb and gunning down worshipers in the deadliest such attack of Egypt's modern history, state media and witnesses said.
No group immediately claimed responsibility, but since 2013 Egyptian security forces have battled a stubborn Islamic State affiliate in the mainly desert region, and militants have killed hundreds of police and soldiers.
State media showed images of bloodied victims and bodies covered in blankets inside the Al Rawdah mosque in Bir al-Abed, west of El Arish, the main city in North Sinai.
Worshipers were finishing Friday prayers at the mosque when a bomb exploded, witnesses said. Around 40 gunmen set up positions outside the mosque with jeeps and opened fire from different directions as people tried to escape.
"Four groups of armed men attacked the worshipers inside the mosque after Friday noon prayers. Two groups were firing at ambulances to deter them, said Mohamed, a witness.
The public prosecutors' office said in a statement 235 people had been killed and 109 more wounded.
Hours after the attack, Egypt's military launched air strikes on targets in mountainous areas around Bir al-Abed, security sources and witnesses said.
"The armed forces and the police will avenge our martyrs and restore security and stability with the utmost force," Egypt's President Abdel Fattah al-Sisi said in a televised address.
"What is happening is an attempt to stop us from our efforts in the fight against terrorism, to destroy our efforts to stop the terrible criminal plan that aims to destroy what is left of our region."
Egypt later said it would delay the opening of the Rafah border crossing to Gaza after the attack due to security concerns. The crossing had been due to open for three days beginning on Saturday.
Striking at a mosque would be a change in tactics for the Sinai militants, who have usually attacked troops and police and Christian churches.
SUFI MUSLIMS
Arabiya news channel and some local sources said some of the worshippers were Sufis, whom groups such as Islamic State consider targets because they revere saints and shrines, which for Islamists is tantamount to idolatry.
The jihadists have also attacked local tribes and their militias for working with the army and police, branding them traitors.
The Sinai branch is one of Islamic State's surviving branches following the collapse of its self-declared caliphate in Syria and Iraq after military defeats by U.S.-backed forces.
Sisi, a former armed forces commander who presents himself as a bulwark against Islamist militancy, convened an emergency meeting with his defense and interior ministers and intelligence chief soon after the attack.
Security has long been one of the key sources of public support for the former general, who is expected to run for re-election early next year for another four-year term.
US President Donald Trump, in a post on Twitter on Friday, called the assault a "horrible and cowardly terrorist attack."
"The world cannot tolerate terrorism, we must defeat them militarily and discredit the extremist ideology that forms the basis of their existence," he addded.
Trump later said he would call Sisi to discuss the attack. A White House statement called on the international community to strengthen its efforts to defeat terrorist groups.
French Foreign Minister Jean-Yves Le Drain also condemned the attack and said Paris stood with its ally.
INCREASINGLY DEADLY
Sinai has been the scene of increasingly deadly attacks as security forces fight against terror networks associated with an ISIS-affiliate.
The ISIS-affiliate in Sinai previously went by the name Ansar Beit Al-Maqdis and is now called Wilayet Sinai. Its roots lie in previous extremist groups including Al-Qaeda that have been involved in terror attacks for a decade, especially in north Sinai.
On November 20, an Israeli soldier was wounded in spillover violence from Sinai.
Terror attacks in Sinai have also become more deadly and complex in the last year. On July 7, ISIS members attacked an Egyptian security checkpoint in el-Barth in north Sinai, killing up to 23 soldiers.
On September 18, members of the security forces were killed during an attack on a convoy passing from El-Arish to Qantara near the village of Toloul. On October 24, two attacks on a Friday killed up to 33 Egyptian security personnel, according to Reuters. One of those attacks was near El-Arish.
Sisi sees the struggle against terror in Sinai as essential to Egypt’s security. When he spoke at the National Police Day in January 2016 he honored a woman whose husband had died in Sinai. Along with the terror threat Cairo faces from the Libyan border, the Sinai is the country’s foremost security challenge.