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'Grim new precedent': Dozens die as sectarian violence erupts in Kabul

A suicide bomber struck a crowd of Shiite worshippers who packed a Kabul, Afghanistan mosque Tuesday. NBC's Atia Abawi reports from Kabul.

KABUL, Afghanistan -- A suicide bomber struck a crowd of Shiite worshippers who packed a Kabul mosque Tuesday to mark a holy day, killing at least 56 people, and a second bombing in another city killed four more Shiites. They were the first major sectarian assaults since the fall of the Taliban a decade ago. 

A Pakistan-based militant group claimed responsibility for the attack.

The attacker blew himself up in the midst of a crowd of men, women and children. The mosque had been packed with worshippers and many who could not fit inside were outside the building.

The blast came shortly after a bicycle bomb near a mosque in the northern city of Mazar-i-Sharif killed at least four people and wounded 21. Another bomb in a motorcycle exploded in the southern city of Kandahar on Tuesday afternoon, injuring six people, but police said that attack did not target Shiites.

Afghanistan has a history of tension and violence between Sunnis and the Shiite minority, but while such attacks have become commonplace in neighboring Pakistan and parts of the Middle East such as Iraq, they have not occurred in Afghanistan.

"Afghanistan has been at war for 30 years and terrible things have happened, but one of the things that Afghans have been spared generally has been what appears to be this kind of very targeted sectarian attack," Kate Clark, from the Afghanistan Analysts Network, told Reuters. "We don't know who planted the bomb yet and it is dangerous to jump to conclusions but if it was Taliban, it marks something really serious, and dangerous, and very troubling." 

Updated at 10:40 a.m. ET: Lashkar-e-Jhangvi al-Alami, a Pakistan-based militant organization, has claimed responsibility for the Kabul suicide attack. In a call to NBC News, someone who claimed to be a spokesman for the group said they had succeeded in their mission to attack Shiites. "It is the first time that someone outside of Afghanistan has claimed responsibility for a attack in the country," NBC News' Mushtaq Yusufzai said.

Updated at 8:50 a.m. ET:  The Ministry of Interior said 55 were killed in Kabul — including two women and four children. Sayed Kabir Amiri, who is in charge of Kabul hospitals, told the Associated Press that more than 160 were wounded in the blast. Police confirm that a second bomb was defused in Mazar-i-Sharif near the one that blew up.

Updated at 7:05 a.m. ET: A Taliban spokesman tells Reuters that the group did not carry out the Kabul or Mazar-i-Sharif attacks.

"People were killed by the enemy's un-Islamic and inhuman activity," Zabihullah Mujahid writes in an emailed statement. He adds that the Taliban "strongly condemns such a cruel, indiscriminate and un-Islamic attack."

Updated at 6:30 a.m. ET: Gareth Price, a senior research fellow at London-based think tank Chatham House, says the attacks may have come now because Afghan and Western forces aren't the easy targets they once were.

"Shia shrines are a softer target than foreign troops or the Afghan army," he tells msnbc.com.

However, discrimination against Shiites --  and in particular the largely Shiite Hazaras --  has deep roots in Afghan history. "All the groups pick on the Hazaras," Price says.

Updated at 6:25 a.m. ET: Citing an official with Afghanistan's health ministry, NBC News reports that the Kabul shrine blast killed 54 people and injured 150 others.

Updated at 5:55 a.m. ET: Afghan officials tell The Associated Press that the death toll in Kabul suicide bombing has reached 48. Mohammed Zahir, chief of the Kabul Criminal Investigation Department, adds that more than 100 people were wounded.

Updated at 5:15 a.m. ET: "The shrine's loudspeaker continued to blast a recitation of the Quran as ambulances carried bodies and wounded away," The Associated Press reports. It adds that the Abul Fazl shrine is located close to the palace where President Hamid Karzai lives. Its blue minaret is one of Kabul's better known landmarks.  

S. Sabawoon / EPA

A body is covered at the scene of an attack near a shrine in Kabul, Afghanistan.

Updated at 4:55 a.m. ET: Britain's Telegraph newspaper reportsthat "Shiites were banned from marking Ashoura in public under the Taliban who ruled Afghanistan until 2001. This year, there are more Ashoura monuments around the city than usual including black shrines and flags."

Updated at 4:35 a.m. ET: Jonathan Boone (@jon_boone), a Kabul-based correspondent for The Guardian, tweetsquoting US General John Allen as describing the attack as "the latest example of the insurgents' blatant disregard for human life."

Updated at 4:25 a.m. ET:  Mohammad Bakir Shaikzada, the top Shiite cleric in Kabul, says that Shiites haven't been attacked in decades in Afghanistan. "This is a crime against Muslims during the holy day of Ashoura. We Muslims will never forget these attacks. It is the enemy of the Muslims who are carrying them out," he said. He says he does not know who could have carried out such an attack.

Updated at 4:15 a.m. ET: Afghan President Hamid Karzai says it is first time that "terrorism" of this kind has occurred in the country on such a religious day, Reuters reports.

Updated at 4:10 a.m. ET: Ahmad Shuja (@ahmadshuja)director of Foundation for Afghanistan, tweets: "My hunch: Today's attacks WON'T, per se, touch off chain of sectarian violence. No Shiite group organized enough or duly experienced."

Updated at 4:00 a.m ET: NBC News cites a health official as saying that at least 50 people were injured in the Kabul blast.

Updated at 3.55 a.m. ET: Mohammad Zahir, head of Kabul's Criminal Investigation Department, tells Reuters that he counted up to 20 bodies at a Kabul hospital, and expected the toll to rise following the explosion at a Shiite shrine in the Afghan capital. A second attack near the main mosque in the northern city of Mazar-i-Sharif killed four people and injured 17 others.

Reuters journalists Mirwais Harooni and Emma Graham-Harrison point out that although "Afghanistan has a history of tension and violence between Sunnis and the Shiite minority ... since the fall of the Taliban the country had been spared the large-scale sectarian attacks that have troubled neighboring Pakistan. The noon bomb in a riverside shrine, in the heart of old Kabul, appears to set a grim new precedent."

Updated at 3:47 a.m. ET: At least 34 people were killed on Tuesday after blasts hit Shiite shrines in Afghanistan during the festival of Ashoura,Al Jazeera English reports citing local media reports and police.

Published at 3:30 a.m. ET: A blast at a shrine in Afghanistan's capital during the Shiite festival of Ashoura killed up to 24 people Tuesday, according to reports.

Meanwhile, four others were killed in the northern city of Mazar-i-Sharif when a bomb on bicycle exploded, Reuters said. The victims included a soldier.

The Kabul explosion was caused by a suicide bomber, Al Jazeera reported. It put the death toll at 24.

However, Hashmatullah Stanekzai, a spokesman for Kabul police, told the Associated Press that it wasn't clear if the explosives were planted in the shrine or if a suicide bomber was behind the attack.

The AP reported that at least 15 had been killed in the attack on the shrine, where worshippers were gathering for Ashoura, the Shiite Muslim holiday marking the death of Hussein, the grandson of Prophet Muhammad.

NBC News, msnbc.com staff, the Associated Press and Reuters contributed to this report.

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