Security forces in Yemen are blaming a suicide bomber disguised as a woman for a deadly attack on a mosque on Thursday. Within hours of the attack, Yemen's branch of the Islamic State (IS) claimed responsibility, saying the group attacked the mosque because it was frequented by members of the Houthi movement.
Accounts of the attack still vary widely, with eyewitnesses saying two suicide bombers were responsible, and security forces pinning the blame on a lone bomber, who was disguised as a woman.
The Houthis, who are from the Zaydi sect of Shiite Islam, seized Sanaa a year ago and forced President Abd-Rabbu Mansour Hadi into exile in Saudi Arabia. Since March, the Western-allied Kingdom has led an Arab alliance trying to restore Hadi to power and drive the Houthis back to their northern stronghold, while IS has exploited the resulting conflict to expand its operations.
IS consider Zaydis to be a heretical religious movement, and in a message on twitter, IS called Thursday's attack, "part of a series of military operations to revenge Muslims against Houthis."
"They went to that mosque for a reason: They knew most of the people inside would be Zaydis," Sheila Carapico, a leading Yemen expert and professor of political science at the University of Richmond, told VICE News. "They did it in order to fan sectarian animosities."
The attack resembled previous bombings by IS militants that have killed hundreds of Zaydis in recent months. Carapico says that IS has taken advantage of the chaos in Yemen to gain a foothold there. "They didn't really exist in Yemen before a few months ago," she said. "Now you see them popping up everywhere."
The exact details of Thursday's attack are still not clear, and eye witness testimony diverges from the official version of events.
Witnesses had earlier described a twin suicide attack on the mosque, where worshippers were celebrating Eid al-Adha, the feast of sacrifice. But Yemeni security forces attributed the attack to single suicide bomber.
Nayef, who lives nearby, said he heard one explosion followed quickly by a second. "We gathered to rescue the wounded. The situation is very painful and blood is everywhere."
The witnesses said the first blast shook the mosque soon after worshippers gathered for prayers. A second suicide bomber detonated his explosives belt when Houthi guards tried to stop him rushing deep inside the mosque.
"We rushed outside and summoned the ambulances," one witness said.
It's unclear why the version related by security forces in Sanaa differs from eyewitness accounts, and Houthi fighters sealed off the area and shouted at onlookers to stay away.
As of Thursday evening, a number of media outlets reported a range of death tolls. Houthi Ansarullah group's website said at least 10 people were killed in the attack. Medics said at least 36 other people were wounded in the attack. Arab media have put the death toll at at least 25.
This was the second attack targeting a mosque run by the Zaydi group in the capital this month.
Earlier this month, at least 28 people were killed and 75 were wounded in twin suicide bombings claimed by the Islamist militant group's Yemen branch targeting a mosque in northern Sanaa.
In March, IS suicide bombers killed at least 137 worshippers and wounded hundreds more in coordinated attacks at two mosques during Friday prayers in the capital.
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