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A homicide car bomber attacked Iranian pilgrims Thursday as they got off tour buses at a Shiite Muslim shrine south of Baghdad, killing 12 people and wounding 39.

The bomber struck about 7:15 a.m. in Kufa, a Shiite holy city 100 miles south of Baghdad, detonating a minivan loaded with explosives behind two buses unloading pilgrims, police said.

CountryWatch: Iraq

Eight of the dead and 22 of the injured were Iranians, said Dr. Munthir al-Athari of the provincial health department. Three of the dead Iranians were women, he said.

At least 19 other people were killed Thursday across Iraq, including 11 men whose bullet-riddled bodies were found in several locations across Baghdad, police said. Several showed signs of torture.

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No group claimed responsibility for the Kufa blast, but suspicion fell on Sunni religious extremists and supporters of Saddam Hussein. Many Sunnis fear the rise of Iraq's Shiite majority will lead to greater influence by Shiite-dominated Iran, with which Iraq fought a bloody war in 1980-88.

"The purpose is clear — to stop pilgrimage. I suspect that the criminal Baathists are behind this act," the local provincial governor, Asaad Abu Kallal, said, referring to members of Saddam's ousted, Sunni-dominated party.

Iran's Foreign Ministry spokesman, Hamid Reza Asefi, denounced the attack as a "barbaric terrorist act" and urged the Iraqi government to find those responsible. He blamed U.S.-led coalition forces, saying they failed to maintain security in Iraq, Iranian television reported.

The U.S. Embassy condemned the bombing "in the strongest terms" and offered condolences to the victims' families.

"The perpetrators of this attack show no respect for Islam and the long tradition of pilgrimage to holy sites," the embassy said in a statement. "Such violence seeks to inflame religious sensibilities and sow discord among Iraq's people."

U.S. officials have offered to discuss the situation in Iraq with Iranian authorities, but Tehran has refused.

Last month, the top U.S. commander in Iraq, Gen. George W. Casey Jr., said Iran had become the main source of materials to make makeshift roadside bombs — an allegation the Iranians deny.

The Kufa attack came a day after the U.S. military predicted an increase in vehicle bombings now that Abu Hamza al-Muhajer, also known as Abu Ayyub al-Masri, has succeeded the late Abu Musab al-Zarqawi as head of Al Qaeda in Iraq.

Al-Masri is an explosives expert specializing in such attacks, Maj. Gen. William Caldwell said. The U.S. military has recorded at least 125 car bombings since al-Zarqawi was killed by a U.S. airstrike.

Prime Minister Nouri al-Maliki returned to Iraq after a regional tour to drum up support for his 24-point national reconciliation plan.

Al-Maliki, a Shiite, told reporters the Sunni leaders of Saudi Arabia, the United Arab Emirates and Kuwait assured him of their support for his initiative, which includes an amnesty offer for insurgents who agree to renounce violence and join the political process.

However, a member of al-Maliki's entourage said the talks were "courteous but not warm," and the leaders of the three countries made clear they would not help the government "until Sunnis have a larger say in running Iraq's affairs."

The delegate spoke on condition of anonymity because of the sensitivity of the issue.

Al-Maliki announced that his government had banned all political activity on university campuses to protect professors and students from being targeted. He said slogans and pictures "that might create disputes among students and professors" would not be tolerated.

He also repeated his call for an independent investigation into the alleged rape and murder of an Iraqi girl south of Baghdad and the killing of three members of her family in March. Former Army Pfc. Steve D. Green has been charged with rape and four counts of murder, and at least four other U.S. soldiers still in Iraq are under investigation in the attack.

"We said we want an investigation in order to know the facts," al-Maliki said.

He said coalition troops need more cultural awareness training to ensure that those who serve in Iraq "bear no grudge nor recklessness toward people's dignity."

U.S. officials hope that over time, al-Maliki's government of Shiites, Sunnis and Kurds, which took office in May, will manage to win public confidence and calm the insurgency and sectarian tensions so that U.S. troops can begin heading home.

However, U.S. and Iraqi officials acknowledge there has been no significant reduction in the bloodshed and say the struggle to restore stability could be long and difficult.

Reflecting the challenges in trying to secure the country, the provincial council for the increasingly violent southern area of Basra decided to dismiss the police chief, Maj. Gen. Hassan Sewadi al-Saad, saying his performance was inadequate. He was replaced by Brig. Gen. Kadim Amin.

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