Yemen on the Edge

A barrage of suicide bombings struck two mosques in the Yemeni capital of Sanaa on Friday, killing at least 137 and wounding some 350 others attending the typically crowded Friday prayer sessions, according to media reports.

A group describing itself as the Islamic State’s Yemen affiliate claimed responsibility for the attacks, according the SITE Intelligence Group, which tracks online jihadi activity. The attacks targeted Houthi mosques in the capital, and online statements called them the “tip of the iceberg that is coming.” If the claim of responsibility is authentic, it would be the Islamic State’s first attack in Yemen. Pentagon spokesman Col. Steve Warren said the claim of responsibility has not yet been confirmed.

Four suicide bombers struck the Badr and al-Hashoosh mosques in Sanaa, which in September was seized by Houthi rebel fighters who belong to the Zaidi offshoot of Shiite Islam. Hard-line Islamic State theology — which hews to extremist Sunnism — considers Houthis as heretics. At the Badr Mosque, one attacker set off his bomb in a crowd of worshippers. When the victims fled the mosque in a panic, a second bomber detonated his explosives among those trying to leave the building. Among the dead at Badr was a Houthi spiritual leader, Murtadha al-Muhatwari.

Two bombers also attacked al-Hashoosh Mosque. According to the New York Times, citing witness reports, one bomber hid his explosives in a fake cast on his leg. He detonated his explosives when stopped at a checkpoint outside the mosque. The other bomber exploded his bomb inside the mosque.

The twin attacks Friday represent the bloodiest in Yemen’s recent history, which has been marked by factional fighting between various rebel and terrorist groups. But mosques have typically not been targeted, and the explicit strike against Houthi religious activity may open up a new chapter in the country’s conflict, one marked by sectarian bloodletting.

Yemen has an active, capable al Qaeda affiliate — al Qaeda in the Arabian Peninsula (AQAP) — but that organization has openly disavowed the Islamic State. Friday’s claim of responsibility by the latter group raises the possibility that the Islamic State, which is also known as ISIS, ISIL, and the Arabic name Daesh, is trying to establish itself as the pre-eminent jihadi group in Yemen.

According to SITE, AQAP released a statement Friday denying involvement in the attack on the Sanaa mosques, saying that it follows al Qaeda leader Ayman al-Zawahiri’s guidance not to target mosques and other public places “out of concern for the lives of innocent Muslims, and to prioritize the paramount interests.”

“ISIS has been arguing that they are the only jihadist force that will really take the fight to the Houthis,” said Thomas Joscelyn, senior editor of the Long War Journal, which focuses on U.S. counterterrorism efforts. “They have even directly attacked AQAP’s jihadist credentials by arguing that AQAP is soft on the Houthis.”

Contrary to the arguments of the Islamic State, AQAP has attacked Houthi targets but has refrained from attacks such as Friday’s brutal bombings. Those attacks, Joscelyn said, are “part of a campaign by ISIS to say that they are the real anti-Shiite jihadist force throughout the Middle East, and that al Qaeda is soft when it comes to anti-Shiite violence.”

In recent days, fighting has gripped Yemen, as special forces troops loyal to former President Ali Abdullah Saleh, who is allied with Houthi rebels, tried to seize control Thursday over the airport in the port city of Aden. Forces loyal to the current president, Abed Rabbo Mansour Hadi, who has fled to Aden after being ousted from Sanaa by the Houthis, repelled the assault. Later the same day, airstrikes targeted Hadi’s presidential compound.

At the same time, the Islamic State has stepped up its pace of attacks. On Wednesday, fighters who are said to have been loyal to the group attacked a museum on Tunis, killing 23 people before security forces ended the siege.

“What we’ve seen really throughout that arc from Northern Africa and then coming across into Yemen is a number of pre-existing terrorist groups who have chosen to pledge allegiance to ISIL, who have chosen to rebrand themselves as ISIL,” Warren, the Pentagon spokesman said. “We believe that this is often out of a desire to increase their own notoriety and to gain access to additional resources.”

Indeed, Friday’s attack echoes the Islamic State’s entry into other battlefields and its use of brutal violence to usurp other jihadi groups. “If they have more high-level attacks like this it could make foot soldiers think twice and possibly defect, like we have already seen with Jabhat al-Nusra to IS in Syria or Ansar al-Sharia in Libya to IS in Libya,” said Aaron Zelin, a fellow at the Washington Institute for Near East Policy and the founder of the blog Jihadology, which tracks jihadi statements and ideology.

As the Islamic State’s reach has spread, the United States and its allies have struggled to cut off the group’s financing from oil sales, extortion, and kidnapping for ransom. International investigators at the Financial Action Task Force said at the end of February that while U.S. airstrikes have damaged the group’s oil revenue, more needs to be done to target “middlemen, buyers, carriers, traders and routes” of the militant group’s oil trafficking.

Now, U.S. counterterrorism finance officials are worried about the Islamic State sending money to support terrorist groups in other countries. The U.S. Treasury Department said Friday that a new 26-country alliance to fight Islamic State financing would focus not only on keeping money from flowing to IS, but also on preventing the group “from providing financial or material support to foreign affiliates in an effort to expand its global ambitions.”

Foreign Policy staff writers Kate Brannen and Jamila Trindle contributed reporting to this article.

Correction, March 20, 2015: An earlier version of this article misstated the name of Aaron Zelin’s blog. It is Jihadology, not Jihadica.

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