In Iraq, gunmen on Saturday attacked the country's largest oil refinery, killing four workers and forcing the facility north of Baghdad to shut down completely. Police said, at least four attackers entered the Baiji oil refinery early on Saturday morning and killed two engineers and two technicians and planted about 10 bombs around one of the production units. The explosion caused a large fire. Refinery officials said it could take two years to fix the damage caused by the attack. The five production units at the Baiji refinery produce 150,000 barrels per day of gasoline, benzene and kerosene.