Refinery workers, witnesses and an Iraqi Army officer reported the seizure of Iraq’s biggest oil refinery by Sunni extremists on Wednesday after army helicopter gunships failed to repel their attack. But other Iraqi officials, including the commander of the garrison defending the refinery in Baiji, asserted that fighting was still going on inside the extensive facility, shut down by the violence. The battle in Baiji, 130 miles north of Baghdad, came as the Obama administration, which extricated American troops from Iraq less than three years ago, was weighing a more muscular response, including airstrikes, to help the besieged government of Prime Minister Nuri Kamal al-Maliki. Foreign Minister Hoshyar Zebari said Wednesday in Saudi Arabia that Iraq had asked for American airstrikes, according to Al Arabiya television. That would make Mr. Zebari the first top Iraqi official to publicly confirm that request, reported by The New York Times […]