As foreign jihadists rally around the cause of Syria's rebels, TIME meets two factions of Islamist fighters seeking to overthrow the Assad regime and set up a political state in their image

Rania Abouzeid for TIME

The al-Qaeda flag was propped up in a barrel painted with the three-starred Syrian revolutionary banner in the middle of the road at a makeshift checkpoint between the northern Syrian towns of Binnish and Taftanaz in Idlib province. The checkpoint was unmanned — not especially surprising, given the dry mid-afternoon heat and the lethargy sometimes brought on early in the Muslim holy month of Ramadan.

But what was surprising was how openly the flag was displayed. It was white, unlike the more familiar black monochrome inscribed with “No God but God” in white lettering, above the circular seal of the Prophet Muhammad. But no matter the color, the implications were the same: that elements of al-Qaeda or the group’s supporters were present in this part of Syria.

There has been much speculation about whether Islamic radicals have gained a foothold in the chaotic battlefield that is Syria today. They have, albeit a small one. While there are jihadists, both foreign and local, inside Syria, their presence should not be overstated. At this stage, they remain a minor player in the conflict. But as Karl Vick’s story in the Aug. 6 issue of TIME (subscription required) relates, should the conflict spiral out of hand, their role may grow exponentially.

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In late January, the jihadist group Jabhat al-Nusra li Ahl Ash-Sham, or the Support Front for the People of Syria, announced its formation and goal to bring down the regime of President Bashar Assad. In the months since, it has claimed responsibility for many of the larger, more spectacular bombing attacks on state security sites, including a double suicide car bombing in February targeting a security branch in Aleppo that left some 28 dead.

Little is known about the shadowy group beyond that it is headed by someone using the nom de guerre of Abu Mohammad al-Golani (Golani is a reference to Syria’s Golan Heights, occupied by Israel.) Some say the group is a regime creation, to prove Assad’s assertion that he is fighting terrorists, while others say it is an offshoot of the al-Qaeda group the Islamic State of Iraq.

A foot soldier in the movement told TIME that it is neither. “We are just people who follow and obey our religion,” the young man, Ibrahim, said. “I am a mujahid, but not al-Qaeda. Jihad is not al-Qaeda.”

It took weeks of negotiations to secure an interview with a member of the movement, the first time anyone from the group has talked to the media. Higher-ups in the Jabhat declined to be interviewed but agreed to let Ibrahim, a 21-year-old Syrian, be interviewed.

The Jabhat has a presence in at least half a dozen towns in Idlib province as well as elsewhere across the country, including strong showings in the capital of Damascus and in Hama, according to the Jabhat member and other Islamists who are in contact with senior members of the group.

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Bespectacled, with a wispy beard and thin mustache, Ibrahim said he joined the group eight months ago. He was recruited by his cousin Ammar, the military operations commander for their unit and a Syrian veteran of the Iraq war who fought alongside his Sunni co-religionists against the American invaders. (Ammar declined to be interviewed.)

Dressed in a deep aqua zippered track top and black track pants that were rolled up above his ankles, the young man did not look as menacing as some of his colleagues, with their short pants, above-the-ankle galabiyas and long beards. In addition to his self-identification as a member of the Jabhat, several Free Syrian Army (FSA) rebels who know him — as well as townsfolk who know his conservative Sunni family — confirmed that Ibrahim is part of the extremist group.

“Our specialty is explosives, [improvised explosive] devices. Most of our operations are explosions using [IEDs], placing them on roads, blowing up cars by remote detonation,” he said. On the night TIME spoke to him, several members of the Jabhat were in a remote field, in the final stages of testing a homemade rocket devised with the help of Syrian veterans of the Iraq war.

The device was a copper-lined shaped charge that can penetrate armor. When the device ignites, the copper element superheats enough to pierce a tank. “It’s a very simple idea, but it works,” Ibrahim said, adding that the device was the work of the Jabhat’s engineering branch. “There’s a killing branch. I’m in the killing and chemical branch,” he said, explaining that the chemical branch was responsible for obtaining fertilizers and other components of the IEDS.

There were 60 men in Ibrahim’s unit, he said, headquartered in a nondescript building that flew two white flags bearing a stylized Muslim shahada — “There is no God but God and Muhammad is the messenger of God.” (Once again, it’s more common to see the shahada printed in white on a black background. The local printer, a sympathizer, said he reversed the colors “so that people don’t think we have al-Qaeda here.”)

Jabhat members maintained a low profile and kept to themselves, townsfolk said, and rarely ventured outside their outpost except to head to battle. “The shabab [young men] prefer to remain in the shadows, unseen. They won’t come forward,” Ibrahim said. Their low profile enabled some members “not known to the security forces” to pass through checkpoints, especially in and around Damascus and the northern commercial hub of Aleppo, which is currently facing aerial bombardment from Assad’s forces as well as encirclement by an approaching armored column. The secrecy extended to the group’s members. “We don’t really like to accept people we don’t know. We don’t need foreigners,” Ibrahim said, although he admitted that there were some foreign jihadists in his group, from Kuwait, Libya and Kazakhstan.

He said he was fighting because he wanted to “live in freedom.” His idea of freedom, however, was an Islamic state free of “oppression” by members of Assad’s privileged sect, the Alawites. “The Alawites can do what they want and we have no say. That’s why we are fighting, because we are oppressed by them,” he said. “We are nothing to them. They are the head, and we are nothing.”

In another town in northern Idlib, another jihadist — belonging to a different group — shared Ibrahim’s goal of an Islamic state. “Abu Zayd” is a 25-year-old Shari’a graduate who heads one of the founding brigades of Ahrar al-Sham, a group that adheres to the conservative Salafi interpretation of Sunni Islam.

He said minorities had nothing to worry about in a future Islamic state, despite the increasingly sectarian nature of some of the violence that has convulsed Syria. “Let’s consider that Syria becomes something other than Islamic, a civil state,” he said. “What is the role of the Alawites in it? What is the position of a Christian, a Muslim in it? They are all under the law, and it will be the same in an Islamic state. We are just exchanging one law for another.”

The young Syrian, with his neatly trimmed beard, dressed in military pants and a blue T-shirt, looked more like a member of the FSA than a Salafist. His facial hair was not fashioned in the manner of some Salafists, who shave their mustaches. (Interestingly, many FSA members have taken to wearing Salafi-style beards while not adopting the ideology. “It’s just a fashion,” one person told me, by way of explanation.)

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The Ahrar started working on forming brigades “after the Egyptian revolution,” Abu Zayd said, well before March 15, 2011, when the Syrian revolution kicked off with protests in the southern agricultural city of Dara’a. The group announced its presence about six months ago, he said. Abu Zayd denied the presence of foreigners, even though TIME saw a man in the group’s compound who possessed strong Central Asian features. “Maybe his mother is,” Abu Zayd said unconvincingly. “We are not short of men to need foreigners.”

Regardless, foreigners are coming across into Syria. One prominent Syrian smuggler in a border town near Turkey said that he had ferried 17 Tunisians across the night before. It was a marked uptick in his business. He said he hadn’t seen many foreign fighters for about a month prior to the Tunisians. “Before that, every day there were new people, from Morocco, Libya and elsewhere,” he said. (In the course of several hours of waiting to cross back into Turkey, I saw at least a dozen Arabs who were clearly not Syrian and were identified as foreigners by the smuggler.)

It’s unclear how large the Jabhat and Ahrar are, given their shadowy natures, but it’s clear that their activities are becoming more public. Both participate in operations alongside regular FSA units, although some FSA commanders remain suspicious of them and jealous of the deep Gulf pockets that are funding them. “Where were the Islamists when the revolution started?” reads a spray-painted line on the wall of one town in Idlib. The response, spray-painted beneath it, is equally curt: “In prison.”

Abu Mohammad, a local FSA commander with 25 men, said he dealt with the Jabhat because he needed their “explosives, bullets and other things … They have experience that I can benefit from, and I can also give them some help, information that benefits them.”

Abu Mohammad said he preferred the Jabhat to the “more showy” Ahrar. “If you ask [the Ahrar] for a device, they will give you a camera so you can film [the explosion], and they take credit for it,” he said. Still, he wasn’t really sold on the Jabhat either. “I am one of those people who is afraid of extremism,” he said. “I told [the Jabhat], It’s possible that perhaps one day we will stand armed against each other because of your activities. If they intend to do to us what happened in Iraq, it’s wrong.”

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Iraq’s al-Qaeda elements imposed their strict interpretation of Islam on the local Iraqi communities they claimed they sought to protect in Anbar province and other predominantly Sunni areas of the country after the 2003 U.S.-led invasion. They antagonized the local Sunnis until they rose up against al-Qaeda and, with U.S. help, expelled it by force from their communities.

A few weeks ago, a Jabhat flag was raised in one of the towns in Idlib province during a demonstration on a Friday following prayers. A group of locals scuffled with members of the Jabhat before they removed the flag.

The Ahrar have also had run-ins with some locals. “A week ago, the Ahrar kidnapped a guy who sold liquor and destroyed his alcohol,” said Mohammad, a 20-something opposition activist. “We told the Ahrar, ‘Release him, or we will protest against you. We will forget about fighting the regime, we will fight you.’ ” The man was released and a compromise reached; he could continue selling alcohol, but not to fighters. “We agreed to this,” Mohammad said, “not for religious reasons, but because it made sense strategically.”

“They need social protection,” Mohammad added. “We told them, ‘If the army comes into our town, who will take you into their homes? Some might tell the army about you.’ That frightened them.”

Other opposition members detest the presence of foreigners among them. Ahmad, also in his 20s, said he stumbled on Libyans training on the outskirts of his town. The activist had a camera but didn’t film the training. The handful of Libyans were enraged nonetheless, and threatened to break his camera. Ahmad said he told them, “ ‘This is my country, not yours. You can leave your weapons and you can go home.’ They aren’t helping us. We don’t need them.”

Still, there are some who welcome the help from jihadists, Islamists, foreigners and locals, given the continuing, grinding 17-month conflict. “I don’t care if the devil intervenes,” said Ayoush, a woman in her 60s. “I don’t want somebody to tell me to cover my face, but we just want to finish this. Enough.” Some say there’s a reason the Islamists have emerged mid-conflict, and not at the start, and that the failure of the international community to decisively act created the conditions that some Islamists have managed to exploit.

Abu Zayd, the Ahrar commander, insists that his men “are not scary” and that the Iraqi experience with armed Islamists can’t be replicated in Syria “because the Iraqi people are not the Syrian people.” Still, he warned that his group would not be sidelined by other elements of the revolution. “We are part of this society, part of this revolution, part of the armed struggle. How can you reject a segment of your society?”

Ibrahim, the member of Jabhat, said the local population had nothing to fear from more religiously conservative Syrians with arms. “People are afraid of the Jabhat. We haven’t harmed anyone here. We are organized and we follow the chain of command. The FSA isn’t even like that,” he said. “Maybe that’s why there is a Jabhat.”

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