15 June 2014
Last updated at 11:00
Iraqi government forces, backed by Shia Muslim and Kurdish militias, are reportedly holding back an advance by Sunni militants north of Baghdad.
A number of towns have been retaken from the rebels, but they still control the key cities of Tikrit and Mosul.
In one town that changed hands, Ishaq, security forces said they had found the incinerated bodies of 12 policemen.
A US aircraft carrier has been deployed to the Gulf in response to the escalating violence.
US Secretary of State John Kerry has warned that American assistance in tackling any Islamist offensive will only succeed if Iraqi leaders are willing to put aside their differences.
The BBC’s Jim Muir, reporting from Iraq, says government forces are building up in the city of Samarra, apparently preparing for a counter-offensive designed to drive rebels out of Saddam Hussein’s hometown, Tikrit, to the north.
Sunday morning saw three Iraqi soldiers and three Shia militiamen killed in a mortar attack on a military recruitment centre near the city of Baquba, north-east of Baghdad.
And in an overnight clash in the town of Jalawla, a government helicopter strike killed seven Kurdish fighters who had moved into positions evacuated earlier by Sunni rebels. Iraqi government officials said the attack was a mistake.
Many Sunni rebels are fighting under the banner of the Islamic State in Iraq and the Levant (ISIS), an offshoot from al-Qaeda.
Iraq’s most senior Shia cleric, Grand Ayatollah Ali al-Sistani, has issued a call to arms to fellow Shia, and there are reports that thousands have already joined militias.
There are reports that thousands of men have joined Shia militias
At the scene: John Simpson, BBC News, Baghdad
On my way into the BBC office [on Sunday] I bumped into a government minister who I know and he told me that there was a real state of panic here a few days ago. Thursday in particular, he said, nobody knew what to say, they could scarcely speak to each other they were so nervous.
But since then, the idea that Shia fighters, Shia volunteers should come forward and back the army up has restored a certain amount of balance here. He said that the government feels a lot more settled at the moment.
Of course you could say that’s a problem for the future of this country, if one religious group is setting out to fight another one – and that blatantly. But that is something else, something for the future. For the moment it seems that there is a bit of a sense that things are settling down.
Struggle for Iraq: In maps
Is this the end of Iraq?
The USS George HW Bush carries dozens of fighter jets
US Defence Secretary Chuck Hagel ordered the USS George HW Bush, which carries dozens of fighter jets, to be moved from the North Arabian Sea to the Gulf.
It is accompanied by the guided-missile cruiser USS Philippine Sea and the guided-missile destroyer USS Truxtun.
However, President Obama has insisted that no US troops will be deployed on the ground in Iraq.
Correspondents say Washington is frustrated with Iraqi Prime Minister Nouri al-Maliki and his Shia-led government for ignoring the concerns of Sunnis and Kurds.
Iranian President Hassan Rouhani said on Saturday he had offered direct assistance to Baghdad, but denied that he had sent troops to fight in Iraq.
However, BBC Persian’s regional analyst Kasra Naji has been told that more than 130 of Iran’s Revolutionary Guards have arrived to provide training and advice. An Iranian general is also reported to be in the capital.
General Qassem Suleimani, the top commander of Iran’s Quds Force, is said to be organising Iraqi Shia militia groups that are loyal to Iran.
Iran has said it could be prepared to work with the US, despite the bitter enmity between the two countries, to fight Sunni insurgents in Iraq.
Meanwhile, former UK Prime Minister Tony Blair has insisted that the 2003 Anglo-US invasion of Iraq is not to blame for the violent insurgency now gripping the country.
Speaking to the BBC, he said there would still be a “major problem” in the country even without the toppling of Saddam Hussein in 2003.
ISIS in Iraq
- The Islamic State in Iraq and the Levant (ISIS) has 3,000 to 5,000 fighters, and grew out of an al-Qaeda-linked organisation in Iraq
- Joined in its offensives by other Sunni militant groups, including Saddam-era officers and soldiers, and disaffected Sunni tribal fighters
- ISIS has exploited the standoff between the Iraqi government and the minority Sunni Arab community, which complains that Shia Prime Minister Nouri Maliki is monopolising power
- The organisation is led by Abu Bakr al-Baghdadi, an obscure figure regarded as a battlefield commander and tactician
Are you in Saadiya, Jalawla or Baghdad? Have you been affected by the latest developments? You can email [email protected] using the title ‘Iraq’.
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