Islamist militants launched a Wednesday morning assault on Iraqi’s largest oil refinery, in the northern town of Baiji. Iraqi sources and refinery employees reported machine-gun fire and mortar attacks at two of the facility’s three main entrances, starting at 4 a.m. local time. Foreign staff were evacuated Tuesday, shutting down the production of some 300,000 barrels of oil per day, much of it for local consumption. There were reports of militants destroying stores of oil after entering the complex.