Members of al-Qaeda-affiliated al-Nusra Front move toward their positions during an offensive to take control of the northwestern city of Ariha from forces loyal to Syrian President Bashar al-Assad. (Ammar Abdullah/Reuters)

Al-Qaeda affiliates are significantly expanding their footholds in Syria and Yemen, using the chaos of civil wars to acquire territory and increase their influence, according to analysts, residents and intelligence officials.

The gains have helped the terror group’s affiliates become major players in the countries and have complicated efforts to resolve the conflicts. Al-Qaeda offshoots could also be gaining sanctuaries to eventually plan attacks against the United States and Europe, analysts say.

In Syria, al-Qaeda’s wing, Jabhat al-Nusra, plays a leading role in a new rebel coalition that has captured key areas in the northwestern part of the country. In Yemen, al-Qaeda in the Arabian Peninsula (AQAP) has seized parts of the country’s largest province, territory that includes military bases, an airfield and ports.

“Al-Qaeda is becoming more deeply entrenched in Syria, and it is gaining significant momentum in Yemen, and the global focus on ISIS has distracted from the expansion of this other radical, transnational group,” said Fawaz Gerges, professor of Middle Eastern politics at the London School of Economics, using an acronym for the Islamic State.

Although there is little evidence that the two al-Qaeda affiliates are collaborating, both are adopting similar strategies of expanding where they can in the shadows of more powerful insurgent groups, analysts say. At the same time, the two branches of al-Qaeda are trying to position themselves as more palatable brands of radical Islam among citizens in Yemen and Syria who feel threatened by the Houthi rebels and the Islamic State.

Though U.S. aircraft are targeting both affiliates, only AQAP is known to have carried out attacks against the West. Jabhat al-Nusra has concentrated most if not all of its energy on the Syrian civil war.

The militants in Syria and Yemen are avoiding the sort of brutality that has distinguished the Islamic State, which split from al-Qaeda last year. The shift appears to be an attempt to win local support and avoid the kind of international military action that the Islamic State is facing, analysts say.

Al-Qaeda’s leaders “are attempting to operate under the radar as part of an adaptive strategy that they see as a way to compete with and outlast ISIS,” Gerges said.

A U.S.-led coalition targeted the Islamic State after it captured a vast swath of territory in Iraq and Syria, declared a caliphate and provoked global outrage with beheadings and other vicious acts. The proclamation of a caliphate was a direct challenge to al-Qaeda, which has aspired to lead Muslims around the world.

Al-Qaeda push in Yemen

In Yemen, AQAP has quietly exploited a war between pro-government forces and Shiite rebels to seize chunks of the southern Hadramaut province, including its capital, Mukalla. AQAP fighters also are battling the rebels, known as Houthis, farther east in Bayda province, although they have not taken control of much territory there.

AQAP is perhaps al-Qaeda’s most powerful affiliate, tied to several bomb plots aimed at the United States, including an unsuccessful effort to blow up a ­Detroit-bound plane in 2009.

Fighters from Al-Qaeda's Syrian affiliate Al-Nusra Front drive in the northern Syrian city of Aleppo flying Islamist flags on May 26, 2015. (Fadi Al-Halabi/AFP/Getty Images)

In recent years, the Yemeni military had launched offensives against AQAP, often with the help of the United States. But the Yemeni army has split, with some units siding with the Houthis. The remaining pro-government forces are focused on fighting the Houthis, not AQAP.

The complex war in Yemen now also involves the Saudis, who have been bombing Yemen to try to drive back the Shiite Houthis, whom they see as proxies of their rival, Shiite Iran. But the Saudis are not targeting AQAP, which comprises Sunnis.

“Why would Saudi attack them if they’re effectively on the same side in this war?” said a Yemeni intelligence official, who spoke on the condition of anonymity, citing security concerns.

AQAP took over Mukalla and surrounding areas without a fight. In the chaos after the fall of the Yemeni government in February and the start of the Saudi air war two months ago, military units in the area abandoned their positions, residents said. Yemen’s president, Abed Rabbo Mansour Hadi, fled to Saudi Arabia but is still recognized internationally as Yemen’s leader.

Residents of Mukalla say that AQAP’s militants have seized banks and gained control over the town council, the judiciary and nearby military installations, which hold battle tanks and heavy artillery.

The residents of Mukalla said AQAP has refrained from imposing strict interpretations of Islamic law, such as banning Arabic music and Western fashions, as the group did when it briefly established an “emirate” in the Yemeni province of Abyan in 2011. The following year, the Yemeni army expelled the AQAP militants with the help of U.S. military advisers and drone strikes.

Now, AQAP’s mostly Yemeni militants are trying to build relationships in Hadramaut by promoting the group’s fighters as a bulwark against Houthi rebels, said Saleh al-Dwaila, a tribal leader in Mukalla who opposes AQAP. Dislike of the Houthis runs especially deep in Yemen’s predominantly Sunni south. “AQAP have been trying to play it carefully here in Mukalla,” Dwaila said.

Katherine Zimmerman, an expert on AQAP at the American Enterprise Institute, said the group has gradually asserted control over parts of Yemen, such as Hadramaut, where the Houthi rebels are not fighting. In other provinces, such as Bayda, AQAP militants are trying to win favor with locals by battling the insurgents, she said.

“What we’re seeing today in eastern Yemen is much more similar to what Jabhat al-Nusra is doing in Syria,” Zimmerman said, adding that it is “a safe assumption” that the affiliates are coordinating with al-Qaeda’s senior leadership.

She said that AQAP’s leader, Nasir al-Wuhayshi, who once worked as Osama bin Laden’s ­secretary, maintains ties with al-Qaeda’s senior leaders.

In an interview last month, the leader of the Syrian al-Qaeda affiliate, Jabhat al-Nusra, acknowledged that he takes orders from Ayman al-Zawahiri, the Egyptian who replaced bin Laden as al-Qaeda’s chief. Those orders include refraining from attacking the West “for the moment,” said Abu Mohammed al-Jolani, a nom de guerre.

Jabhat al-Nusra

In Syria, his group — also known as the al-Nusra Front — has fought as part of a new rebel coalition called the Army of Conquest, which has seized key territory in northwestern Idlib province from government forces. Gains in Idlib have brought the rebels to the border with Turkey, a NATO member, and within reach of the Syrian government’s coastal strongholds to the west. Nusra militants also are fighting alongside rebel groups in areas near the borders with Jordan, Lebanon and Israel.

The Army of Conquest has benefited from enhanced coordination among Saudi Arabia, Turkey and Qatar to overthrow Syria’s president, Bashar al-Assad. In recent weeks, those countries have provided weapons and logistical support to the rebel coalition, which also includes other Islamists as well as moderate rebels.

Nusra started to acquire significant territory in northern Syria last year, defeating moderate rebel groups that had lost popularity because of reputations for corruption and ineffectiveness. Nusra, which fields predominantly ­Syrian fighters, is seen by many in the country as more honest and potent against Assad’s forces.

Those attributes have helped Nusra weather the challenge posed by the Islamic State, which fields many foreign fighters who are often unfamiliar with local customs.

The Obama administration has watched with alarm the expanding influence of Nusra, according to a senior administration official who spoke on the condition of anonymity because the policy issues are sensitive.

“The advance in the north worries us. Our goal is not for the regime to lose ground to the benefit of Nusra and Ahrar al-Sham,” he said, referring to another major group that coordinates closely with Nusra but is not an al-Qaeda affiliate.

There are moderate groups represented in the coalition seizing territory in the north, he noted. But Nusra is clearly a major player, if not the leading one.

Before Nusra joined the Army of Conquest, it had often imposed harsh measures in the areas it controlled, executing adulterers and arresting people for blasphemy.

Other Army of Conquest members have pressured Nusra to rein in its extremist behavior, said Charles Lister, an expert on the al-Qaeda affiliate at the Brookings Doha Center.

Abu Khalil, an anti-regime activist who monitors fighting in Idlib province, said protests broke out in the northwestern village of Salqin last year after Nusra fighters imposed conservative dress requirements on women and exerted control over village councils. The demonstrations helped persuade the group to soften its policies, added the activist, who asked that his real name not be used, citing safety concerns.

Ali al-Mujahed in Sanaa, Yemen, Sam Alrefaie and Suzan Haidamous in Beirut, and Liz Sly and Greg Miller in Washington contributed to this report.

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