CAIRO/ISMAILIA (Reuters) - Egyptian President Abdel Fattah al-Sisi cut short a visit to Ethiopia for an African Union summit on Friday after Islamic State's Egyptian wing claimed the killing of at least 30 soldiers and police officers in the Sinai Peninsula.
The four separate attacks on security forces in North Sinai on Thursday night were among the bloodiest in years and the first significant assault in the region since the most active Sinai militant group swore allegiance to IS in November.
Militant attacks in Sinai, while far from Cairo and tourist attractions, has crimped government efforts to project an image of stability to woo back foreign investors and tourists driven away by frequent political violence since a popular uprising four years ago that overthrew veteran autocrat Hosni Mubarak.
Sisi left Addis Ababa after meeting with the Ethiopian premier following the AU summit's opening session, an Egyptian official there told Reuters.
Most of Thursday's casualties occurred in the bombing of a military hotel and base in al-Arish, the heavily guarded Sinai provincial capital.
Security sources in Sinai said three military planes left al-Arish for Cairo on Friday morning carrying 30 body bags, some of them containing corpses left in pieces by the bomb blasts. They said at least five men were in critical condition and the death toll was likely to rise.
Two children, one of them 6 months old, died on Friday from wounds suffered on Thursday night as soldiers fought militants in a village near Sheikh Zuweid, close to the Gaza Strip and Israel's border, local medical sources said.
An army statement on Friday did not give a final death toll. It said the Supreme Council of the Armed Forces had met and was determined to continuing supporting the state's efforts to complete a "roadmap for achieving security and stability."
A major investment conference is set for March, where the government hopes to attract billions for huge infrastructure projects, and Egypt will also launch long-awaited parliamentary elections the same month.
But attempts to reinstate stability in the Arab world's largest country have been impeded in part by the Sinai-based Islamist insurgency that has intensified since the army ousted elected president Mohamed Mursi of the Muslim Brotherhood in mid-2013 after mass unrest over his rule.
Hundreds of security force members have been killed since.
The Brotherhood denies links to the insurgents but the government makes no distinction between the two groups.
"All of us are in sorrow over what happened yesterday in Sinai but Egypt is paying the price of confronting terrorism and extremism," Sisi said in a statement carried by the state news agency MENA.
The most active group, Ansar Bayt al-Maqdis, changed its name to Sinai Province last year when it swore allegiance to Islamic State, the ultra-radical Sunni militant group that has seized swathes of Iraq and Syria, drawing U.S.-led air strikes.
A daily news broadcast released via Islamic State Twitter feeds said Thursday's attacks had been led by "men of the Islamic State".
Egyptian soldiers and police are often targeted at outposts outside the widely desolate, rugged Sinai's main towns. But the assault on military facilities in al-Arish could signal an escalation in their capabilities, according to Zack Gold of the Institute for National Security Studies in Tel Aviv.
This week had already been a bloody one in Egypt. More than 25 people were killed at the weekend when security forces fired at protesters angered by what many perceive as a police state re-established by Sisi since Mursi's fall.
After two attacks in October in which 33 security personnel were killed, Egypt declared a state of emergency in the area where Sinai borders Gaza and accelerated plans to create a buffer strip.
Sisi, who as army chief toppled Mursi, says Egypt is fighting a war on terrorism and enjoys the support of Western and Gulf Arab allies.
Additional reporting by Omar Fahmy and Mahmoud Mourad in Cairom, Edmund Blair in Addis Ababa; Editing by Mark Heinrich