Arish, Egypt, Muharram 10, 1437, Oct 23, 2015, SPA -- A roadside bomb went off Friday in Egypt's Sinai Peninsula, killing a police officer and injuring three others, dpa quoted a security official as saying. The explosion occurred when a police armoured vehicle hit the bomb in al-Arish, the capital city of northern Sinai, the official added on condition of anonymity. No one has claimed responsibility for the attack.