Insurgents advanced on Iraq’s biggest oil refinery on Wednesday, a day after overrunning the city of Mosul in a spectacular show of force which triggered an exodus of half a million refugees.
Sunni militants from an al Qaeda splinter group overran Mosul – Iraq’s second-largest city - on Tuesday following a weekend of heavy fighting.
The fall of the city has struck a humiliating blow to Prime Minister Nouri Al-Maliki's Shiite-led government: security forces fled their posts, leaving government buildings, police stations, the airport and even their weapons for the militants' taking.
Maliki has ordered a state of emergency, amid mounting calls from the U.S., U.N. and others for an urgent and unified political response to the escalating crisis.
The U.S. said it is "deeply concerned" about the situation, with White House spokesman Josh Earnest urged Iraq's leaders to "step up to the plate" to preserve security. U.N. Secretary General Ban Ki-moon also urged “all political leaders to show national unity against the threats facing Iraq.”
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Iraq’s Foreign Minister Hoshyar Zebari urged a quick response to the “serious, mortal threat” facing his country and also called on his country’s leaders to come together, according to The Associated Press.
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Zebari said that there will be closer cooperation between Baghdad and the Kurdistan regional government to “work together and try to flush out these foreign fighters," the news agency reported.
The International Organization for Migration said Wednesday that its teams on the ground estimate that the weekend's violence has displaced more than 500,000 people in and around Mosul, a former insurgent stronghold 225 miles from Baghdad.
A vehicle curfew has forced many of the internally displaced to flee on foot amid reported indiscriminate shelling, the Geneva-based organization added in a statement.
IOM warned of a deteriorating humanitarian situation, with parts of the city lacking drinking water and running low on food.
The violence has inflicted high numbers of civilian casualties, it added, saying mosques are being converted into clinics to treat the wounded.
Less than three years after the U.S. troop withdrawal, violence in Iraq has reached levels not seen since before the U.S.-led invasion.
Much of that violence has been attributed to militants from the al Qaeda breakaway group known as the Islamic State of Iraq and the Levant (ISIL), which has waged a bloody battle to shake confidence in the Shi'ite-led government.
"What happened is a catastrophe by any measure"
Maliki has drawn fierce criticism for failing to stem the bloodshed and maintain security, with the assault on Mosul the latest indication that Iraq’s U.S.-trained security forces are outmatched.
When the militants attacked Mosul, many fled – abandoning their posts, weapons and armored vehicles, shedding uniforms as they ran. Images from the city showed thick plumes of black smoke rising in the sky and the burnt-out shells of security vehicles.
"Their positions were easy prey for terrorists," said Usama Nuajifi, Speaker of Iraq’s Parliament. "What happened is a catastrophe by any measure."
ISIL has been steadily gaining ground in Iraq, galvanized by the civil war in neighboring Syria which has yielded a steady flow of recruits, fighters and weapons across the border.
It also has capitalizing on the deep feelings of disenfranchisement among Sunnis, who feel marginalized by what many describe as divisive and sectarian policies from Maliki's government.
With Mosul resting in militant hands, ISIL now has advanced on the key oil town of Baiji, according to Reuters.
On Wednesday, Baiji resident Jasim al-Qaisi told the news agency that the militants had also asked senior tribal chiefs in Baiji to persuade local police and soldiers not to resist their takeover. "Gunmen contacted the most prominent tribal sheikhs in Baiji via cellphone and told them: 'We are coming to die or control Baiji, so we advise you to ask your sons in the police and army to lay down their weapons and withdraw,” he told the news agency.
The Baiji refinery can process 300,000 barrels per day and supplies oil products to most of Iraq's provinces and is a major provider of power to Baghdad.