Egypt mourned on Saturday as the death toll from a gun and bomb assault at a mosque in the Sinai Peninsula soared above 300, including children, in the deadliest attack the country has witnessed. The army said warplanes had struck militant hideouts in the insurgency-wracked North Sinai in retaliation.

According to the state prosecution, up to 30 militants in camouflage flying the Islamic State (IS) group’s black banner had surrounded the mosque and proceeded to massacre the worshippers during weekly Friday prayers. Twenty-seven children were among the dead, it said.

IS has not claimed responsibility for the attack, but it is the main suspect as the mosque is associated with followers of the mystical Sufi branch of Sunni Islam whom it has branded heretics.

Funerals for the victims were held overnight and many were buried unwashed in their bloodied clothes, according to the Islamic burial practices for martyrs, security and medical officials said.

President Abdel Fattah al-Sisi declared three days of mourning and vowed to “respond with brutal force” to the attack, among the deadliest in the world since the September 11, 2001 attacks on the United States. “The army and police will avenge our martyrs and return security and stability with force in the coming short period,” he said in a televised speech, as reported by http://www.dailymail.co.uk.