* Political tensions high
* Thousands of Iranian pilgrims visiting Iraqi holy sites
* Car bombs in holy cities Kerbala, Najaf; oil city Basra
(Recasts, adds Basra explosion, Iran commemts)
By Aseel Kami
BAGHDAD, Nov 8 (Reuters) - Three car bombs killed at least 15 people in Iraq on Monday, including two attacks targeting Iranian pilgrims, as political leaders met to try to break an eight-month deadlock over a new government.
Two of the bombs targeted Iranian pilgrims in Iraq's holy Shi'ite cities of Kerbala and Najaf, killing at least 10 people, while a third struck a bustling street of shops and restaurants in Iraq's southern oil hub of Basra.
The deputy head of Basra's provincial council, Ahmed al-Sulaiti, and an Iraqi army source both put the toll from the Basra explosion at five killed and 42 wounded. The Iraqi army source had initially said 12 people were dead.
"The explosion was caused by a car bomb which killed five people and wounded 42," Sulaiti told Reuters, adding these were initial figures.
"This explosion is linked to the explosions in Najaf and Kerbala, and we accuse those groups from al Qaeda and the Ba'athists."
A source at Basra's operations command said the explosion had been caused by a bomb attached to a truck. The head of police in Basra, Major General Adil Daham, said the explosion had been caused by a suicide car bomber.
Tensions have been rising in Iraq as the country remains in a political vacuum eight months after an inconclusive election. A parliamentary session is due on Thursday.
Although violence has dropped from the height of sectarian warfare in 2006-07, insurgents are still capable of launching a series of often devastating attacks. More than 100 people were killed last week when gunmen raided a church and a series of bomb blasts struck mainly Shi'ite areas of Baghdad.
U.S. troops are scaling back their presence in Iraq before a full withdrawal next year.
Seven people were killed and 34 wounded by a blast at one of the entrances to Kerbala, site of two of the holiest shrines in Shi'ite Islam, said Mohammed al-Moussawi, head of the Kerbala provincial council. Four of the dead were Iranians, he said.
"It was a car bomb. There were Iranian pilgrims in the area. They were targeted," Moussawi said.
In Najaf, a car bomb killed three people and wounded 10 when it exploded near buses transporting Iranian pilgrims to the revered Imam Ali shrine, a hospital official said. A police source put the toll at five dead and 16 wounded and said most of the casualties were Iranian.
Another official at Najaf's health office said eight people, including three Iranians, were killed by the bomb, and 19, seven of them Iranians, were wounded.
Hundreds of thousands of Iranian religious tourists have visited Shi'ite holy sites in neighbouring Iraq since the 2003 U.S.-led invasion toppled Sunni dictator Saddam Hussein.
Saddam crushed insurrections by Iraq's Shi'ite majority, banned Shi'ite religious festivals and fought an eight-year war with Shi'ite power Iran.
The pilgrims are often targeted by Sunni Islamist groups such as al Qaeda in Iraq, which view Shi'ite Muslims as apostates.
While there was no immediate claim of responsibility, the attacks bore the hallmarks of a weakened but still lethal insurgency, which wants to reignite sectarian war and abhors what it sees as Iranian influence on Iraq's Shi'ite leaders.
The head of Iran's Haj and Pilgrimage Organisation, Ali Qaziasgar, said it would consider stopping sending pilgrims to Iraqi shrines if security was not assured.
"If Iraq fails to provide Iran's pilgrims with full security, Iran will re-examine the idea of sending pilgrims to Shia shrines in Iraq," Qaziasgar told state radio.
Iraq's political factions met in the capital of the Kurdish region on Monday to try to break the deadlock over the formation of a new government which has left the country in limbo since the March 7 election. [ID:nLDE6A70WX]
Incumbent Prime Minister Nuri al-Maliki, a Shi'ite, is close to securing a second term but is still trying to win over leaders of a Sunni-backed cross-sectarian alliance. (Additional reporting by Khalid Farhan in Najaf, Aref Mohammed in Basra and Hossein Jaseb in Tehran; Writing by Michael Christie and Serena Chaudhry; Editing by Charles Dick)
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