Cairo - Two policemen were killed by a roadside bomb on Saturday in Egypt's restive Sinai Peninsula, according to a local security source. Another police conscript was injured when a police vehicle struck the bomb in the North Sinai city of Arish, the source said anonymously as he was unauthorized to speak to media. No group has yet claimed responsibility for the attack, but an Islamist insurgency in the Sinai has gained pace since the military toppled President Mohamed Mursi of the Muslim Brotherhood in 2013 following mass protests against him.