Fighters from the Islamic State of Iraq and the Levant took control a day earlier of much of Mosul, the country's second-largest city, in a major blow to the authority of the country's Shiite government and a sign of Iraq's reversals since U.S. forces withdrew in late 2011.
The Sunni militants also gained entry to the Turkish consulate in Mosul and held captive 48 people, including diplomats, police, consulate employees and three children, according to an official in the office of Turkish Prime Minister Recep Tayyip Erdogan.
An estimated half a million residents fled the economically important city.
Tikrit residents reached by telephone said the militant group had taken over several police stations in the Sunni-dominated city. They spoke on condition of anonymity for fear of their safety.
As night fell, several hundred gunmen were in Tikrit, with clashes still taking place between the insurgents and military units on its outskirts, said Mizhar Fleih, the deputy head of the municipal council of nearby Samarra.
Two Iraqi security officials confirmed that Tikrit, the capital of Salahuddin province, was under the control of the ISIL, and said the provincial governor was missing. Tikrit is 130 kilometers (80 miles) north of Baghdad.
The major oil refinery in Beiji, located between Mosul and Tikrit, remained in government control, the officials said, speaking on condition of anonymity because they weren't authorized to talk to reporters.
Turkish officials trying to free the captives at the consulate in Mosul have been in direct contact with the militants as well as Iraqi officials and believe that the hostages are safe, said an official in Erdogan's office. He spoke on condition of anonymity because of he was not authorized to comment to reporters on the sensitive issue.
Security officials in the Turkish consulate in Mosul had allowed the militants in after being threatened with explosives, the official said.
Turkish officials trying to free the captives have been in direct contact with the militants as well as Iraqi officials and believe that the hostages are safe, he added.
Turkish officials did not make any public comment on the seizure, but the state-run Anadolu Agency reported that Erdogan convened an emergency Cabinet meeting. Foreign Minister Ahmet Davutoglu canceled meetings in the U.S. to return home to coordinate a response, the ministry said.
U.N. Secretary-General Ban Ki-moon strongly condemned the abduction, saying he was "shocked" by the news. "This is totally unacceptable," Ban said.
Mosul's fall was a heavy defeat for Prime Minister Nouri al-Maliki and a sign of Iraq's reversals since U.S. forces left the country in late 2011. The Islamic State of Iraq and the Levant, which wants to set up a militant enclave in the region, has been capturing territory in both Iraq and neighboring Syria in that country's civil war.
Al-Maliki said the massive security failure in Sunni-dominated Ninevah province that allowed militants to seize Mosul was the result of a "conspiracy," and that those members of the security forces who fled rather than stand up to the militants should be punished.
He stopped short of assigning direct blame, however, choosing to focus instead on plans to fight back — without detailing the specifics.
"Today, the important thing is that we are working to solve the situation," a stern-faced al-Maliki said. "We are making preparations and we are regrouping the armed forces that are in charge of clearing Ninevah from those terrorists."
The stunning assault in Mosel by the al-Qaida-inspired group saw black banner-waving insurgents raid government buildings, push out security forces and capture military vehicles as residents fled for their lives.
Mosul is the capital of Ninevah province. It and the neighboring Sunni-dominated province of Anbar share a long and porous border with Syria, where the Islamic State is also active.
Ninevah Gov. Atheel al-Nujaifi told reporters that "Mosul is capable of getting back on its feet and getting rid of all the outsiders," and said authorities planned to mobilize residents into militias that would play a role in retaking the city.
There were no immediate estimates on how many people were killed in the rampage, which sent an estimated 500,000 people fleeing the city and surrounding areas, according to the International Organization for Migration.
Some simply crossed to the eastern bank of the Tigris River to avoid the worst of the fighting, while others made their way to the Ninevah countryside or sought refuge in the nearby semiautonomous Kurdish region.
Getting into that area has grown trickier, however, with migrants without family members already in the enclave needing to secure permission from Kurdish authorities, according to the IOM.
Foreign Minister Hoshyar Zebari said the fall of Mosul to insurgents must bring the country's leaders together and deal with the "serious, mortal threat" facing Iraq.
"We can push back on the terrorists ... and there would be a closer cooperation between Baghdad and the Kurdistan Regional Government to work together and try to flush out these foreign fighters," he said on the sidelines of a diplomatic meeting in Athens.
Mosul residents reached Wednesday said gunmen went around knocking on doors, reassuring people they would not be harmed and urging civil servants to return to work. The situation appeared calm but tense, said the residents, who would not give their names out of concerns for their safety.
In an eastern section of the city, 34-year-old Ali Sameer said mosques in his neighborhood were calling on people to return to work, especially those in public services.
Al-Maliki has pressed parliament to declare a state of emergency over the Mosul attack.
Echoing al-Maliki, Ninevah governor al-Nujaifi accused senior security force commanders of providing Baghdad with false information about the situation in Mosul and demanded they stand trial.
Speaking from the northern Kurdish city of Irbil where he took refuge, he said smaller armed groups had joined the Islamic State during the fight for control of the city.
Violence raged elsewhere in Iraq on Wednesday.
Police and hospital officials said a suicide bomber set off his explosive belt inside a tent where tribesmen were meeting to solve a tribal dispute in Baghdad's Shiite Sadr City neighborhood, killing 24 and wounding 41. A car bomb in the district killed four more and wounded nine, while in the northern district of Khazimyah, a car bomb blast in a commercial street killed six people and wounded 14.
A car bomb struck Shiite pilgrims heading to the holy city of Karbala, killing four people and wounding 10, and another killed three people and wounded 12 in a town south of Baghdad.
All officials discussed the attacks on condition of anonymity because they were not authorized to speak to the media.
Associated Press Writers Adam Schreck in Dubai, United Arab Emirates, Elena Becatoros in Athens, Qassim Abdul-Zahra in Boston, Desmond Butler in Istanbul and Edith M. Lederer at the United Nations contributed to this report.
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