More than 20 bombs hit cities and towns across Iraq Thursday, killing at least 36 and wounding more than 100, police and hospital sources said, raising fears of sectarian strife in a country keen to show it can now maintain security. 

In Baghdad, three car bombs, two roadside bombs and one suicide car bomb hit mainly Shiite areas in what looked like coordinated attacks, killing 15 people and wounding 61, the sources said. 

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 Two car bombs and three roadside bombs aimed at police and army patrols in the northern oil city of Kirkuk killed eight people and wounded 26, police and hospital sources said. 

"I was trying to stop traffic to let a police patrol pass. When it passed, a car bomb exploded and I fell on the ground and police took me to the hospital," a policeman wounded in the face and chest told Reuters as doctors tended his wounds. He declined to be named. 

Heightened tension between Shiites, Sunnis and Kurds in the fragile coalition government since U.S. troops withdrew in December has raised fears of a return to sectarian violence of the kind that pushed Iraq to the brink of civil war a few years ago. 

The country is less violent than at the height of that conflict in 2006-07, but bombings and killings still happen daily, often aimed at Shiite areas and local security forces. 

Kirkuk, home to Arabs, Kurds, Turkmen and others, is at the heart of a long-running dispute between the central government and the autonomous Kurdish region, which claims the city and the region's rich oil reserves. 

The rift between Baghdad and the Kurds recently worsened when the Kurdistan Regional Government said it was halting oil exports because the central government was not paying oil firms operating in the north. 

The government of Prime Minister Nuri al-Maliki is anxious to show it can keep the country secure and attract investment following the withdrawal of U.S. troops. 

Baghdad hosted an Arab League summit last month, its first for 20 years, and it passed off relatively peacefully amid a massive security lockdown.

Attacks in Iraq are mostly blamed on Sunni Arab insurgents who have refused to lay down arms after the withdrawal of U.S. forces in December.

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Updated at 8:11 a.m. ET: A suicide car bomber struck early Monday at the gates of Jalalabad airport in eastern Afghanistan, killing nine people in a large blast, officials said.

Among the dead were six civilians, two airport guards and one soldier, Mohammad said. Another six people were wounded, he said.

An AP photographer saw at least four destroyed cars at the gates of the airport.

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The Afghan Taliban claimed responsibility for the suicide attack, that they also say killed a number of U.S. soldiers and members of the Afghan interior ministry, a spokesman told NBC News.

"Our suicide bomber carried out suicide attack at a time when the U.S. troops opened the main entrance for change of the night time shift at the airport. Besides American soldiers, a number of Afghanistan interior ministry personnel working (with) the U.S. troops were also killed in the attack," the Taliban spokesman Zabihullah Mujahid told NBC News.

He said it was revenge of the desecration of holy Quran allegedly by U.S. forces at the Bagram airbase.

But NATO forces spokesman Capt. Justin Brockhoff said that no international forces were killed in the early morning attack and that the installation was not breached by the blast.

Escalating violence
The blast comes a day after demonstrators hurled grenades at a U.S. base in northern Afghanistan, and a gun battle left two Afghans dead and seven NATO troops injured Sunday in the escalating crisis over the burning of Muslim holy books at an American airfield.

More than 30 people have been killed, including four U.S. troops, in six days of unrest. Still, the top U.S. diplomat in Afghanistan said the violence would not change Washington's course.

"Tensions are running very high here, and I think we need to let things calm down, return to a more normal atmosphere, and then get on with business," Ambassador Ryan Crocker told CNN's "State of the Union."

"This is not the time to decide that we're done here," he said. "We have got to redouble our efforts. We've got to create a situation in which al-Qaida is not coming back."

Story: Eight US soldiers wounded in Afghan NATO base attack

The attack on the base came a day after two U.S. military advisers — a lieutenant colonel and a major — were found dead after being shot in the head in their office at the Interior Ministry in the heart of the capital. The building is one of the city's most heavily guarded buildings, and the slayings raised doubts about safety as coalition troops continue their withdrawal.

The incident prompted NATO, Britain and France to recall hundreds of international advisers from all Afghan ministries in the capital. The advisers are key to helping improve governance and preparing the country's security forces to take on more responsibility.

A manhunt was under way for the main suspect in the shooting — an Afghan man who worked as a driver for an office on the same floor as the advisers who were killed, Interior Ministry spokesman Sediq Sediqi said. He did not provide further details about the suspect or his possible motive.

Story: Afghan officer sought in connection with US slayings

The Taliban claimed that the shooter was one of their sympathizers and that an accomplice had helped him get into the compound to kill the Americans in retaliation for the Quran burnings.

Afghanistan's defense and interior ministers were to visit Washington this week, but they called off the trip to consult with other Afghan officials and religious leaders on how to stop the violence, Pentagon press secretary George Little said. The Afghan officials had planned to meet with Defense Secretary Leon Panetta and Joint Chiefs Chairman Gen. Martin Dempsey.

The protesters in Kunduz province in the north threw hand grenades to express their anger at the way some Qurans and other Islamic texts were disposed of in a burn pit last week at Bagram Air Field, north of Kabul.

 

The Associated Press contributed to this report.

Police say a suicide bomber has killed 16 people and wounded 26 in a crowd of police recruits who were leaving their academy in eastern Baghdad.

It is the latest strike on Iraqi security officials who are often targeted by insurgents seeking to underscore how vulnerable the country remains.

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Iraqi police said the bomber detonated his car Sunday outside the fortified national Police Academy compound when the crowd of recruits came out and began walking down the street.

Officials at three nearby hospitals confirmed the casualties, although there were conflicting reports about the exact death toll.

"I can see body parts scattered on the ground and boots and berets covered with blood. Many cars were set ablaze," a policeman working at the academy told Reuters.

The Associated Press and Reuters contributed to this report

A suicide bomber detonated his explosive vest outside a mosque in a Shiite neighborhood Friday in Pakistan's northwestern Kurram tribal region, killing at least 26 people, government officials said.

Three more people were killed when police shot at protesters from the Shiite community after the bombing in Parachinar, the main town in Kurram, an official said. A curfew was imposed in the town.

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The bomber struck outside the mosque in a busy market after Friday prayers, in the latest attack by Sunni militants against minority Shi'ites.

Kurram, the only part of Pakistan's border region that has a significant Shiite population, has been racked by sectarian violence between Sunni and Shi'ite tribes. The Taliban and al Qaeda's virulent anti-Shiite ideology has meant years of bloody fighting.

Fazal Saeed, leader of a breakaway faction of the Pakistani Taliban, claimed responsibility for the latest attack in Kurram, near the Afghan border.

"We have targeted the Shiite community of Parachinar because they were involved in activities against us," he told Reuters by telephone from an undisclosed location.

"We also warn the political administration of Parachinar to stop siding with the Shi'ite community in all our disputes."

Shiite Muslims are a minority sect of Islam, arising from a dispute over the successor to the Prophet Mohammad 1,400 years ago. Many extreme Sunni Muslims consider them apostates.

Saeed was part of the Tehrik-e-Taliban Pakistan (TTP) but broke away last year after disputes with the umbrella militant group's leadership.

He is said to have close ties with the Haqqani militant group, one of the most feared factions of the Afghan Taliban.

The TTP, al Qaeda, and the Afghan Taliban movement fighting Western forces in Afghanistan are entrenched in Pakistan's northwestern tribal areas. All have been involved in anti-Shiite activities for years.

They continue to have strongholds in the region despite a series of military operations in the last few years.

Pakistan's army and air force have been conducting operations against militant groups in Kurram since the beginning of the year. Dozens have been killed in fierce fighting this month.

The blast came as Pakistan's foreign minister said it would be "preposterous" for Afghanistan to expect Islamabad to deliver the Taliban's leader to the negotiating table, as talks between the two countries on the peace process ended with little sign of progress.

The apparent gridlock shows the difficulties inherent in the peace process, which the United States is strongly pushing as a way to end the 10-year-old Afghan war and allow it to withdraw most of its combat troops by 2014 without the country further descending into chaos.

Pakistan is seen as key to the process because Taliban chief Mullah Omar and other senior commanders are believed to be based in the country. Islamabad has close historical ties to the group but has always denied that the Taliban leadership is based within its borders. Analysts say Pakistan can either help the talks or act as a spoiler.

It's unclear whether Afghan President Hamid Karzai asked for access to Omar during his current visit to Islamabad, and he made no public mention of the cleric. But he has called on Pakistan in the past to facilitate contact with the insurgent group's leaders.

Leaders from Afghanistan, Pakistan and Iran held a three-way summit in Islamabad over the past two days that focused on Taliban peace talks, including steps Pakistan could take to help the process, and other regional issues. The summit ended Friday.

However, Pakistani Foreign Minister Hina Rabbani Khar indicated her government was still uncertain on exactly what Afghanistan wanted, saying "they have not conveyed that clarity to us."

Karzai also seemed to indicate the process going forward was uncertain.

"What we need now is to formulate a policy that is actionable and implementable, and actually act upon it," Karzai said at a press conference featuring Pakistani President Asif Ali Zardari and Iranian President Mahmoud Ahmadinejad. Khar's comments came as she spoke to reporters after the press conference.

The foreign minister cautioned against Kabul expecting too much in terms of Pakistan providing access to the Taliban's leaders.

"If you have unrealistic, almost ridiculous expectations, then you don't have common ground to begin with," said Khar.

Khar said that any expectation that Pakistan can deliver the Taliban's chief for talks is "not only unrealistic, but preposterous."

Pakistan and Afghanistan have long had a troubled relationship, one that grew more difficult last year when a suicide bomber assassinated former Afghan President Burhanuddin Rabbani in Kabul. He had been serving as Afghanistan's envoy to Taliban peace talks, and Afghan officials accused Pakistan of playing a role in the killing — allegations it denied.

There have been some signs that momentum for Taliban peace talks has been growing.

The Taliban are setting up an office in the tiny Gulf state of Qatar in the first step toward formal negotiations. Also, the Obama administration is considering releasing five top Taliban leaders from the U.S. detention center in Guantanamo Bay as a starting point for talks.

But the process has also been riddled with rumor and uncertainty.

The Associated Press and Reuters contributed to this report.

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