Now how much was Iran involved in the operation?
Iraq forces break siege of main oil refinery

Latest update : 2014-11-15
Iraqi pro-government forces on Saturday broke the siege of the country’s main oil refinery, where security forces had held out for months against the Islamic State jihadist group, officials said.
“Iraqi forces… reached the gate of the refinery,” the governor of Salaheddin province, Raad al-Juburi, told AFP.
Three officers confirmed that Iraqi forces had reached Baiji refinery in the country’s north, which once handled some 300,000 barrels of oil per day, filling some 50 percent of national demand.
Militants from the Islamic State organization (IS) who had besieged the refinery for months without managing to penetrate it, withdrew on Saturday from the perimeter of the strategic complex, an army officer told Reuters news agency.
The officer said the IS militants had removed roadside bombs they had planted and fled.
Strategic victory
The advance to the refinery came a day after another significant victory for Iraqi forces, who recaptured the strategic town of Baiji, just to the south.
More here. H/T: Fjordman