Egypt Vows 'Vicious War Against Terrorism' in Revenge for Sinai Attacks

Egyptian authorities promised today that they would wipe out the Sinai Peninsula-based insurgents responsible for a devastating assault on security forces that killed dozens on Wednesday.

Militants from an Islamic State (IS) linked group calling itself Sinai Province launched a series of coordinated attacks on army checkpoints in and around the northern Sinai town of Sheikh Zuweid on Wednesday morning, before besieging the central police station amid heavy fighting that lasted hours.

The military said in a statement that 17 soldiers had died, along with 100 of the attackers, but security and medical officials quoted by the Associated Press and a number of other sources said that at least 64 troops were killed, making it the deadliest battle in the area since 1973's Arab-Israeli war.

The attack involved suicide car bombers and large numbers of gunmen. The state-affiliated el-Watan daily newspaper reported on Thursday that guided missiles, including Russian-made Kornet anti-tank missiles, had been used in the attack along with mortars and heavy machine guns, and that some of the weapons had been smuggled across the Libyan border.

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The armed forces said in a statement that it was waging a "vicious war against terrorism," according to an AFP translation, adding "we will not stop until Sinai is cleansed of all the dens of terror." Spokesman, Brig. Gen. Mohammed Samir released graphic pictures on his official Facebook page showing the camouflage-clad corpses of what it said were militants involved in the attack.

It was the latest incident in a full-blown insurgency that is posing the biggest challenge yet to President Abdel-Fattah el-Sisi's rule. Earlier this week, state prosecutor Hisham Barakat was killed in a Cairo car bombing and militants have killed hundreds of members of the security forces in the Sinai since democratically elected Islamist President Mohamed Morsi was ousted by the military, then headed by Sisi, almost exactly two years ago.

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Since then, the government's "war on terrorism" has failed to curtail it, despite security measures including a night-time curfew, vastly increased troop presence, and a buffer zone along the Gaza border.

A coordinated series of assaults on checkpoint on April 2 killed 15 soldiers, while in January at least 24 people, mostly members of the security forces, died in in a series of bombings and rocket attacks on military and police targets.

Sinai Province, which was formerly known as Ansar Bait al-Maqdis, pledged its allegiance to IS last year.

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But authorities have repeatedly blamed the Morsi's now-banned Muslim Brotherhood for the violence. On Wednesday the cabinet passed a new anti-terror law and asked for a faster appeals process in response to Barakat's death.

Authorities launched a massive crackdown on Brotherhood supporters following Morsi's ouster, killing hundreds and jailing thousands more. It added the group to its terror list in December and sentenced hundreds to death in mass hearings. Morsi himself was also given a death sentence along with other senior members, a verdict which is currently subject to appeal.

Also on Wednesday, special forces killed nine brotherhood members, including a member of Morsi's government in a raid on a Cairo apartment, the Associated Press said.

Follow John Beck on Twitter: @JM_Beck