Suicide bombings at two mosques in Yemen’s capital killed more than 100 people Friday, the deadliest terror attacks in the country’s history and a sign, just days after an attack in Tunisia, of the spreading jihadist threat across the Middle East.
A group that said it was affiliated with Islamic State claimed responsibility for the attacks on the two mosques in San’a, where suicide bombers detonated explosives just after noon as people gathered for midday prayers, local security officials said. When survivors fled, a second pair of bombs exploded outside the mosques, killing more people. By evening, the official death toll had risen to 135.
San’a Province, a previously unknown Islamic State affiliate, claimed the attacks. They came just a day after Islamic State claimed responsibility for Wednesday’s attack on a museum in the capital of Tunisia that killed 21 people, including 18 foreign tourists. None of those claims could be independently verified.
Kurdish officials said they suspected Islamic State for twin suicide bombs that exploded late Friday among crowds gathered for Kurdish spring celebrations in the northeastern Syrian city of al-Hasakah late Friday, leaving at least a dozen dead and many more injured.
A group claiming loyalty to Islamic State also claimed responsibility for the beheading of 21 Egyptian Coptic Christians in Libya last month, raising the specter of the extremist group’s spread outside its base in Syria and Iraq to challenge other Sunni terrorist groups that have pledged allegiance to al Qaeda.
A statement on San’a Province’s Twitter account said four of its suicide bombers carried out Friday’s attacks on the mosques in San’a and another attack in Saada province, according to a translation by the extremist-tracking SITE Intelligence Group.
By targeting mosques of the Zaidi offshoot of Shiite Islam, the attacks appeared to be aimed at the religious sect of Yemen’s ruling Houthis, a group from the north that is estimated to make up around 30% of the country’s population.
San’a Province’s message decried the Houthis as “polytheists” and promised the operations were “but the tip of the iceberg that is coming.”
If the claim of responsibility is accurate, the attacks would be the first known in Yemen by an Islamic State affiliate. Islamic State extremists took wide swaths of territory in Iraq and Syria starting last summer, and the group is currently the target of a U.S.-led coalition carrying out airstrikes to stop its spread.
Islamic State announced last year that it intended to start a branch in Yemen, but little is known about San’a Province. The elaborate coordination of Friday’s bombings suggested they were the work of a group with training and experience, but San’a Province’s leadership and origins are shrouded in mystery.
The statement from the group claiming responsibility was signed only by “The Media Office of San’a Province.”
The White House said Friday that U.S. officials haven’t confirmed Islamic State’s involvement in the Yemen attack. Josh Earnest, the White House press secretary, said other groups have made similar claims of responsibility for propaganda value, and that American officials are investigating.
“There’s no evidence that there is an operational link” between the attack and Islamic State extremists, Mr. Earnest said, while acknowledging that extremist groups are trying to capitalize on instability in Yemen.
J.M. Berger, a nonresident fellow at the Brookings Institution who studies Islamic State, said the killings showed that while U.S. and allied forces might be fighting Islamic State to a stalemate in Iraq and Syria, the terrorist network’s influence is spreading through the region.
Islamic State extremists “are making a statement that they want to be a global terrorist organization,” he said.
San’a was ill-equipped to handle the casualties after Friday’s attacks, and most of the wounded were transported for treatment in private vehicles. At least a dozen died on the way to hospitals, according to government officials.
People rushed to donate blood, but a lack of capacity at the city’s hospitals left many of the wounded waiting for too long.
“This is the reason for the continuous rise in the death toll,” said Abdullah Shaban, a senior government official.
Another bombing on Friday rocked a government compound in Saada province, a Houthi stronghold where the group’s leader, Abdul Malik Al Houthi, is based. Two people were killed and a third person was in critical condition, two local officials said.
The Houthis overran San’a in September and demanded a larger share of power from the government, led by President Abed Rabbo Mansour Hadi.
After United Nations-brokered negotiations for a political compromise failed to produce a deal, Mr. Hadi abruptly resigned in January. The Houthis put him under house arrest and took control of government two weeks later.
In February, Mr. Hadi escaped house arrest and fled to the port city of Aden, in the primarily Sunni Muslim southern region he hails from. He has since withdrawn his resignation and is rallying support among southern security forces for a comeback.
Amid the spiraling uncertainty, at least a dozen countries, including the U.S., Saudi Arabia and Turkey, have closed embassies and evacuated staff.
Yemen is of strategic significance to the U.S. because of its long-running cooperation with Mr. Hadi’s government against al Qaeda in the Arabian Peninsula, or AQAP, Yemen’s potent al Qaeda offshoot. Those operations, which include drone strikes, have continued despite the political and security turmoil of recent months, although American officials have acknowledged that they have been affected.
Within the Middle East, Saudi Arabia and Iran also have large stakes in the outcome of Yemen’s turmoil. Saudi Arabia, the oil-rich Sunni Gulf monarchy, has given aid to Mr. Hadi, while Shiite Iran—Saudi Arabia’s biggest regional rival—supports the Houthis.
AQAP, a Sunni extremist group opposed by both Mr. Hadi and the Houthis, has claimed responsibility for many terrorist attacks in Yemen, including a suicide bombing in 2012 at a military parade in San’a that killed 101 people. That was at the time the deadliest in the country’s history.
The apparent arrival of Islamic State in Yemen, the Middle East’s poorest country, could put the group into conflict with AQAP, which has a decadeslong history and a base of support among politically disenfranchised Sunni tribes.
Islamic State has demanded in the past that AQAP pledge loyalty to Abu Bakr al-Baghdadi, the group’s leader and self-proclaimed caliph. But AQAP, which the U.S. considers the world’s most dangerous jihadist group, has so far resisted these attempts and criticized its tactics.
The groups could clash if San’a Province is able to expand and demands that AQAP dissolve. Such conflict between Islamic State and other extremist groups has been a feature of its rise in Syria, where it has fought bitterly against the Nusra Front, al Qaeda’s Syrian branch.
Yemenis will resist Islamic State’s expansion into their country, “because their Iraqi way of fighting and killing will not work in Yemen,” said an AQAP member who serves as media liaison.
AQAP has long opposed Islamic State’s brutality. In a 43-minute video released in December, AQAP founding member Nasser bin Ali al-Ansi called Islamic State’s use of beheadings “barbaric propaganda.”
AQAP denied any involvement in Friday’s attacks in a statement on Twitter, citing the guidance of al Qaeda leader Ayman al Zawahiri, “which advises avoidance of targeting the mosques, markets and mixed places to preserve the souls of innocent Muslims.”
The rebuke echoed a 2005 letter Mr. Zawahiri wrote to Abu Musab al-Zarqawi, who was then the leader of al Qaeda in Iraq before the group spun off and created Islamic State.
Mr. Zawahiri demanded Mr. Zarqawi curb the brutality his al Qaeda branch was inflicting on Iraqis, warning it would turn the Sunni population against them. Mr. Zarqawi rebuffed his demands.
Other al Qaeda-linked groups, including in Yemen, have split off and pledged allegiance to Islamic State in recent months as it gained territory and prestige among jihadists. In February, a Twitter statement purportedly by AQAP supporters in central Yemen said they broke allegiance with al Qaeda and were aligning themselves with Islamic State, according to a SITE translation.
U.S. officials also are sifting through information on the attack in Tunisia, where Islamic State’s claim of responsibility is so far unconfirmed.
Friday’s attacks came a day after 13 people were killed during violent clashes at the international airport in the southern port city of Aden. Yemeni special forces loyal to former president and Houthi ally Ali Abdullah Saleh cut off roads to the airport Thursday morning, leading Mr. Hadi to send in government troops.
Troops backed by a column of tanks expelled the special forces after several hours of fighting.
Later on Thursday, the presidential compound in Aden where Mr. Hadi is based was targeted by two airstrikes that were apparently carried out by the Houthi-controlled Yemeni air force. Mr. Hadi fled to a secure location and was unharmed, an aide to the president said.