Mourners grieve near the coffin of a victim killed by a suicide bomber who blew himself up inside a tent filled with mourners in Baghdad, during a funeral in Najaf, south of Baghdad, June 12.

BAGHDAD  —  Iraqi Kurds took control of the northern oil city of Kirkuk on Thursday, June 12, after government forces abandoned their posts in the face of a sweeping Sunni Islamist rebel push towards Baghdad that threatens Iraq’s future as a unified state.

Peshmerga fighters, the security forces of Iraq’s autonomous Kurdish north, swept into bases in Kirkuk vacated by the army, a peshmerga spokesman said.

“The whole of Kirkuk has fallen into the hands of peshmerga,” said Jabbar Yawar. “No Iraqi army remains in Kirkuk now.”

Kurds have long dreamed of taking Kirkuk and its huge oil reserves. They regard the city, just outside their autonomous region, as their historical capital, and peshmerga units were already present in an uneasy balance with government forces.

The swift move by their highly organized security forces to seize full control demonstrates how this week’s sudden advance by fighters of the Al Qaeda offshoot Islamic State of Iraq and al-Sham (ISIS) has redrawn Iraq’s map.

Since Tuesday, black clad ISIS fighters have seized Iraq’s second biggest city, Mosul, and Tikrit, home town of former dictator Saddam Hussein, as well as other towns and cities north of Baghdad. They continued their lightning advance on Thursday, moving into towns just an hour’s drive from the capital.

The Iraqi army has essentially fled in the face of the onslaught, abandoning buildings and weapons to the fighters who aim to create a strict Sunni caliphate on both sides of the Iraq-Syria frontier.

The stunning advance of ISIS, effectively seizing northern Iraq’s main population centers in a matter of days, is the biggest threat to Iraq since U.S. troops withdrew in 2011. Hundreds of thousands of people have fled their homes in fear.

Security and police sources said insurgents now controlled parts of the small town of Udhaim, 90 km (60 miles) north of Baghdad, after most of the army troops left their positions and withdrew towards the nearby town of Khalis.

“We are waiting for supporting troops and we are determined not to let them take control. We are afraid that terrorists are seeking to cut the main highway that links Baghdad to the north,” said a police officer in Udhaim.

In Tikrit, video footage showed dozens of members of a police special forces battalion held prisoner, paraded before a crowd by fighters who overran their base.

Militants have set up military councils to run the towns they captured, residents said.

“They came in hundreds to my town and said they are not here for blood or revenge but they seek reforms and to impose justice. They picked a retired general to run the town,” said a tribal figure from the town of Alam, north of Tikrit.

“’Our final destination will be Baghdad, the decisive battle will be there,’ that’s what their leader of the militants group kept repeating,” the tribal figure said.

Security was stepped up in Baghdad to prevent the ISIS militants from reaching the capital, which is itself divided into Sunni and Shi’a neighborhoods and saw ferocious sectarian street fighting in 2006-2007 under U.S. occupation.

By midday on Thursday insurgents had not entered Samarra, the next big city in their path on the Tigris north of Baghdad.

“The situation inside Samarra is very calm today and I can’t see any presence of the militants. Life is normal here,” said Wisam Jamal, a government employee in the mainly Sunni city which houses Shi’ite pilgrimage site.

The million-strong Iraqi army, trained by the United States at a cost of nearly $25 billion, is hobbled by low morale and corruption. 

Iraq’s parliament was due to hold an extraordinary session on Thursday to vote on declaring a state of emergency, but failed to reach a quorum, a sign of the sectarian political dysfunction that has paralized decision-making in Baghdad.

About 500,000 Iraqis have fled Mosul, home to 2 million people, and the surrounding province, many seeking safety in autonomous Kurdistan, a region that has prospered while patrolled by the powerful peshmerga, avoiding the violence that has plagued the rest of Iraq since the U.S. invasion in 2003.

Maliki described the fall of Mosul as a “conspiracy” and said the security forces who had abandoned their posts would be punished. He also said Iraqis were volunteering in several provinces to join army brigades to fight ISIS.

In a statement on its Twitter account, ISIS said it had taken Mosul as part of a plan “to conquer the entire state and cleanse it from the apostates,” referring to the province of Nineveh of which the city is the capital.

Militants were reported to have executed soldiers and policemen after their seizure of some towns.

In Mosul, 80 Turkish citizens were being held hostage by ISIS, the foreign ministry in Ankara said, after its consulate there was overrun. Turkey threatened to retaliate if any of the group, which included special forces soldiers, diplomats and children, were harmed.

Ambassadors of the NATO defense alliance held an emergency meeting in Brussels at Turkey’s request and Prime Minister Tayyip Erdogan held talks with U.S. Vice President Joe Biden about the developments.

ISIS, led by Abu Bakr al-Baghdadi, broke with al-Qaeda’s international leader, Osama bin Laden’s former lieutenant Ayman al-Zawahri, and has clashed with al-Qaeda fighters in Syria.

In Syria it controls swathes of territory, funding its advances through taxing local businesses, seizing aid and selling oil. In Iraq, it has carried out regular bombings against civilians, killing hundreds a month. 

President Obama said on Thursday that he is looking at all options in helping the Iraqi government. 

“I don’t rule anything out,” Obama said when asked whether the United States is considering drone strikes or any other action to stop the insurgency.

Obama, speaking to reporters at the White House as he met Australian Prime Minister Tony Abbott, said the United States has an interest in making sure jihadists do not gain a foothold in Iraq.

He said there will be short-term immediate actions that need to be done militarily in Iraq, and that his national security team is looking at all options. He said the United States is prepared to take military action when its national security interests are threatened.