Egyptian President Abdel Fattah al-Sisi convened an emergency meeting of his senior defense advisers on Friday just hours after a deadly terrorist attack claimed the lives of at least 28 soldiers in the Sinai Peninsula.
At least 28 security personnel were killed by a car bomb that targeted two armored vehicles stopped at a checkpoint, security sources and Egyptian media reports indicated.
At least 20 soldiers were injured in the attack in the al-Kharouba area northwest of al-Arish, near the border with the Gaza Strip, the sources said.
Eyewitnesses had earlier heard a loud explosion near the Egyptian town of al-Arish in the Sinai Peninsula on Friday afternoon in what appeared to be an attack on a nearby army installation.
Security forces face a jihadist insurgency that has killed hundreds of soldiers and policemen since the army toppled President Mohamed Morsi of the Muslim Brotherhood last year after mass protests against his rule. Most attacks have been in Sinai.
Six soldiers were killed on Sunday by a roadside bomb southwest of al-Arish.
Earlier on Friday, masked men set fire to two cars belonging to the consulate of Saudi Arabia in the Egyptian city of Suez on Friday morning, local security sources and the state news agency reported.
Security sources who spoke on condition of anonymity told Reuters at least four men threw crude fire bombs at the vehicles. State news agency MENA said the cars were parked in a lot in Suez's Arbaeen district.
Saudi Arabia has been a strong backer of Egypt since then-army chief Sisi toppled Morsi last year. The attack appeared to be the first on Saudi property or personnel in Egypt since then.
Major General Tareq al-Gazar, director of security in the city, said authorities were working to identify the attackers.
The Saudi embassy in Cairo declined to comment.
Tens of thousands of Brotherhood supporters have been arrested since Morsi's overthrow.
One person died from a gunshot wound during clashes between security forces and Brotherhood supporters in the impoverished Materiya district of Cairo on Friday afternoon, the website of state newspaper Al-Ahram reported.
The Muslim Brotherhood says it is a peaceful movement but authorities accuse its members of being involved in a Sinai Peninsula-based Islamist insurgency that has killed hundreds of policemen and soldiers in the 15 months since Morsi's overthrow.
Saudi Arabia and Gulf Arab allies United Arab Emirates and Kuwait have given Egypt large-scale aid in cash and petroleum products since Morsi was ousted from power.