Twenty-three Egyptian security agents died and several more were wounded in what appears to be a rocket-propelled grenade (RPG) attack on their vehicle in the Sinai on Monday, sources said. The incident occurred after several explosions on the road, which could have been from mines or heavy artillery, eyewitnesses said. Egyptian authorities are calling it an accident, and have banned reporters and photographers from the Al Arish hospital were the bodies were taken. Earlier on Monday, a communique from al-Qaeda leader Ayman El Zawahry, an Egyptian doctor, appeared online. Zawahry offered himself to the Egyptian government as a mediator in the conflict with Islamist rebels in northern Sinai, which in August left 16 Egyptian border guards dead.