BAGHDAD - Security forces entered Iraq’s largest refinery for the first time on Tuesday after months of battling Islamic State militants who had surrounded it, a police colonel said.

Complete recovery of the Baiji facility could provide critical momentum for government forces charged with restoring stability in a country facing its worst security crisis since dictator Saddam Hussein was toppled in 2003. “The first Iraqi force, the anti-terrorism force called Mosul Battalion, entered Baiji refinery for the first time in five months,” police colonel Saleh Jaber of the Baiji refinery protection force told Reuters.

State television flashed news of the advance and broadcast footage it said was of Iraqi security forces entering the refinery’s gate.

“In this area, terrorists were stationed to the left and right. If God is willing, Baiji will be the main key to liberating each span of Iraq,” the commander of provincial security operations, Abdel Wahab al-Sa’adi, told the broadcaster. US-led air strikes have prevented the Islamist group, which swept through northern Iraq in June almost unopposed by the Iraqi army, from making significant further territorial gains for its self-proclaimed caliphate. Islamic State seized the city of Baiji and surrounded the sprawling refinery during that first advance in June.

Islamic State has stolen oil and petroleum products from areas it controls in an effort to create a self-sustaining Islamic empire, oil officials say.

Prime Minister Haider al-Abadi sacked 26 military commanders this month for corruption in an apparent bid to show the government is serious about improving the performance of the army to counter Islamic State.

The Baiji refinery was producing around 175,000 barrels per day before it was closed, a senior Iraqi official said in June. Iraq’s domestic daily consumption is estimated at 600,000-700,000 bpd.

Iraq believes Islamic State militants have stolen more than one million tonnes of grain from the country’s north and taken it to two cities they control in neighbouring Syria, the agriculture minister has said.

Falah Hassan al-Zeidan said in a statement posted on the Agriculture Ministry’s website on Sunday that the government “had information about the smuggling by Islamic State gangs of more than one million tonnes of wheat and barley from Nineveh Province to the Syrian cities of Raqqa and Deir al-Zor.” Reuters was unable to verify the information. When Islamic State pushed from Syria into northern Iraq in June, they swiftly took over government grain silos in Nineveh and Salahadeen provinces, where about a third of Iraq’s wheat crop and nearly 40 percent of the barley crop is typically grown.

The former head of the Grain Board of Iraq told Reuters in August that Islamic State militants had seized 40,000 to 50,000 tonnes of wheat in Nineveh and the Western province of Anbar and transferred it to Syria for milling.

Meanwhile, the Saudi Interior Ministry has said that tighter security in Saudi Arabia has made it hard for Islamic State to target the government so the militants are instead trying to incite a sectarian conflict via attacks.

Last week the IS leader Abu Bakr al-Baghdadi called for attacks against Saudi Arabia, which has declared Islamic State a terrorist organisation, joined international air strikes against it, and mobilised top clergy to denounce it. “Islamic State and al Qaeda are doing their best to carry out terrorist acts or crimes inside Saudi Arabia,” Major General Mansour Turki, security spokesman for the Interior Ministry, told Reuters. “They are trying to target the social fabric and trying to create a sectarian conflict inside the country.”

Turki said he was not aware of any evidence that it was coordinated with Islamic State operatives outside Saudi Arabia. He said improved government security, such as guards at possible targets, increased border defences and surveillance, have made it much harder for militants elsewhere to organise violence inside Saudi Arabia such as al Qaeda’s 2003-06 uprising which killed hundreds and led to the detention of more than 11,000 people.

Meanwhile, Jordan’s Queen Rania on Tuesday urged support for US-led air strikes against the Islamic State militant group, saying the future of the Middle East and Islam was at stake. “Our silence is the greatest gift” for IS, which has seized large swathes of Iraq and Syria, she told participants at a media summit in Abu Dhabi. “We are complicit in their success,” added the queen.

She is married to King Abdullah II, whose Hashemite kingdom has joined the US-led air campaign against IS in Syria along with Bahrain, Qatar, Saudi Arabia and the United Arab Emirates. “The coalition must be broader... It’s the fight for the future of the Middle East and Islam,” she said. “It’s a fight that we have to win.”