Intensifying violence in the Middle East on Friday stoked fears of an oil-supply disruption in the region, pushing oil prices above $78 a barrel. With oil futures climbing 5 percent in the past week, the Organization of Petroleum Exporting Countries tried to reassure the market by stressing its commitment to "order and stability." Israel widened its offensive on Lebanon on Friday, with fighter bombers blasting the airport for a second day and cutting the main highway to Syria. Hizbullah has fired more than 100 rockets into Israel. More than 51 people have died in two days of violence sparked by the kidnapping of two Israeli soldiers by Hizbullah operatives. While Israel and Lebanon are not involved in the Middle East oil market, the fear is that the conflict could expand in the region, which produces nearly a third of the world's oil and has almost two-thirds of its untapped reserves.