The officials say gunmen sprayed a police lieutenant's car with gunfire today, killing him instantly. Later, assailants shot dead a policeman as he left his home.
The officials spoke on condition of anonymity because they were not authorized to speak to the media.
Today's killings took to at least 12 the number of soldiers and policemen killed in northern Sinai since the weekend.
Egypt has for years been battling militants in Sinai, but the insurgency there intensified after the military's 2013 ouster of Islamist president Mohammed Morsi.