A suicide bomber rammed a vehicle into an intelligence headquarters in Baghdad on Saturday, killing at least 11 people, police and medical sources said.
A police officer said the suicide bomber drove an explosives-laden car into the gate of the Interior Ministry's intelligence headquarters in Karrada district Saturday afternoon, killing six civilians and five security personnel.
He added that 24 other people were wounded. Others put the number of injured at 32.
A medical official confirmed casualty figures. Both officials spoke on condition of anonymity as they were not authorised to brief the media.
The intelligence headquarters is protected by concrete blast walls, but the security forces on guard at its entrance on an often-crowded intersection are easy targets for attack.
There was no immediate claim of responsibility for the blast, but suicide bombings are a hallmark of Sunni jihadists, including those loyal to the Islamic State (IS) group.
The attacks came a day after Shiite militiamen machine-gunned nearly 70 Sunni worshipers at a village mosque in Diyala Province, raising the prospect of revenge attacks as politicians try to form a government capable of countering Islamic State militants.
The apparent revenge attack at the mosque in Diyala province on Friday would increase already significant anger among Iraq’s Sunni Arab minority with the Shiite-led government, undermining an anti-militant drive that requires Sunni cooperation to succeed.
Meanwhile, near Tikrit, a suicide bomber driving a military Humvee packed with explosives attacked a gathering of soldiers and Shiite militias on Friday night, killing nine.
An advance by Islamic State through northern Iraq has alarmed the Baghdad government and its Western allies and drawn air strikes in Iraq for the first time since the withdrawal of American troops in 2011.
Army and police officers said the attack on the Musab bin Omair Mosque in Diyala came after Shiite militiamen were killed in clashes, while other sources said it followed a roadside bomb near one of their patrols.
Doctors and the officers put the toll from the attack, in which worshippers were sprayed with machine gun fire, at 70 dead and 20 wounded.
Two officers had earlier blamed IS for the attack, but the preponderance of accounts point to Shiite militiamen.
The government turned to militiamen to bolster its flagging forces during the IS offensive, sparking a resurgence of groups involved in brutal sectarian killings in past years that will be difficult to dislodge.
Ibrahim Aziz Ali, whose 25-year-old nephew was among those killed, said he and other residents heard gunfire and rushed to the mosque, where they were fired on by snipers.
“We found a massacre” at the mosque, he said.
Five vehicles with images of revered Shiite Imam Hussein were parked at the mosque, Ali said, adding that residents clashed with the militiamen who withdrew when the Iraqi army arrived.
Iraqi premier designate Haidar al-Abadi issued a statement calling for unity and condemning the killings, which may complicate the already-contentious process of forming the country’s next government.
Meanwhile, Washington declared the beheading of an American journalist a “terrorist attack”, upping the stakes in its confrontation with the IS jihadists.
The mosque attack came as the US ramped up its rhetoric over the grisly killing of journalist James Foley, which was carried out by the jihadist group and shown in a video posted online.
In Washington, Deputy National Security Adviser Ben Rhodes said the beheading of Foley “represents a terrorist attack against our country”.
Rhodes also said that paying ransoms to free hostages is “not the right policy”, confirming Washington’s long-standing position amid claims from IS that other countries had paid to have their nationals freed.
In an unanimous statement on Friday, the UN Security Council strongly condemned Foley’s murder as “heinous and cowardly”.
US vice-president Joe Biden said on Friday that Washington would back a federal system in Iraq.
Writing in a Washington Post opinion piece, Biden pointed to “functioning federalism” as an approach to breach the divisions in the country.
Biden is a long-time supporter of the plan under which Iraq would be divided into three semi-autonomous regions for Shiites, Sunnis and Kurds, respectively.
The United States began an air campaign against IS in Iraq on April 8, and has since conducted 93 air strikes, including three against militants in the area of the Mosul dam, the country’s largest, on Friday.
Pentagon chiefs warned of the dangers of IS  and said operations against it in Syria may be needed.
“They marry ideology and a sophistication of strategic and tactical military prowess,” US Defence Secretary Chuck Hagel. “This is beyond anything we have seen.”
Foley’s killing has stoked Western fears that territory seized by the militants in Syria and Iraq could become a launchpad for a new round of global terror attacks.
The US State Department estimates that about 12,000 foreign fighters from at least 50 countries are in Syria.
Foley, a 40-year-old freelance journalist, was kidnapped in northern Syria in November 2012. His employer GlobalPost said his captors had demanded a 100-million-euro (HK$1.03 billion) ransom.
GlobalPost CEO Philip Balboni said his team had never taken the demand seriously, and US State Department deputy spokeswoman Marie Harf insisted: “We do not pay ransoms.”
His captors had also sent Foley’s family a taunting and rambling email threatening to kill him.
In the execution video, released online, a black-clad militant said Foley was killed to avenge US air strikes against IS.
The man, speaking with a clear south London accent, paraded a second US reporter, Steven Sotloff, in front of the camera and said he too would die unless President Barack Obama changes course.
Reuters, AP and AFP