Egyptian security forces killed 12 militants and arrested 92 in a continuing crackdown in Sinai, the army said in a statement carried by State TV on Monday.

Egypt's air force also destroyed 60 militant targets, the statement said, part of a campaign to crush Islamist insurgents blamed for a string of attacks.

President Abdel Fattah al-Sisi, who is seeking re-election in March, ordered the armed forces in November to defeat militants within three months after an attack on a mosque killed more than 300 people, the deadliest such incident in the Arab world's most populous country.