Egypt's President has given his security forces a three-month deadline to restore security and stability in troubled northern Sinai following a massacre by Islamic militants there that killed 305 people last week. <br/><br/>Abdel-Fattah el-Sissi spoke during a televised address today in a ceremony marking the birthday of Islam's Prophet Muhammad. The massacre, which took place as worshippers were praying in a village mosque on Friday, was the deadliest terrorist attack in Egypt's modern history.<br/><br/>El-Sissi authorised his new chief of staff, Maj. Gen. Mohammed Farid Hegazy, to use "all brute force" against the militants, who have been battling security forces in Sinai for years.