Khalil Hamra / AP Free Syrian Army soldiers stand guard at a checkpoint in the northern town of Ariha, on the outskirts of Idlib, Syria, on June 10, 2012

Abboud Barri jiggles the dog tags as if they belonged to animals being raised in a puppy mill. “I have a lot of these,” Barri says. “Any buyers?” He is joking. The tags belong to human beings, soldiers of the Assad regime who are now held captive or were killed by Barri, a local commander of one of the franchise groups of the rebel Free Syrian Army (FSA). Unlike some other militia leaders, Barri says he isn’t interested in demanding ransom from his captives’ families. He says he keeps the ID tags so those families know “to look for them in hell.”

He keeps the eight military-issued dog tags in the right pocket of his sand-colored cargo pants; they are war booty from his unit’s recent assault on a loyalist checkpoint in Idlib province.

Barri, along with 20 or so other men from several different FSA units in Idlib, is reclining on deep red cushions spread out on plastic straw mats under a sprawling almond tree in the Jabal al-Zawya region in northern Syria. Some of the men laugh as they recount some of Barri’s wilder antics, like the time he set out on an extremely perilous but heroic journey to the besieged town of Rastan, halfway between Homs and Hama, to deliver much needed bags required for blood transfusions. Others recall how Abu Rabieh, a respected revolutionary figure in Idlib province, refused to give Barri a gun, fearing what the former agricultural worker might do with it. Abu Rabieh was shot dead late last year in an ambush. A few months later, Barri formed a military unit, which he now says includes some 58 men. “He was always a risk taker,” one of the men later says about Barri. “In the beginning of the revolution, before there was so much destruction, we didn’t want hot-blooded risk takers who didn’t carefully study their actions. Now it doesn’t matter.”

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As Barri speaks, one of his phones beeps. Like a few others in his possession, the device belongs to one of his prisoners. It has received a text message from the captive’s father, wishing him a happy ‘Id al-Fitr, the Muslim holiday that marks the end of the holy month of Ramadan. After several minutes, the phone rings. It is the father. “Read him the fatiha,” Barri says dismissively to the parent, referring to a Muslim prayer often recited for the dead. “May God have mercy on his soul.” Some of the other men, who admire Barri’s bravado, are taken aback by his coldness. “I was very uncomfortable when I heard him say that,” one of the men says. “I was sad for the father.”

War is dehumanizing, and civil wars in particular can brutalize a society in ways that fundamentally alter its very nature. Neighbors become enemies; differences — social, economic, religious — become magnified as a means to confirm the otherness of the enemy. Local accents and surnames can reveal sectarian identities and, by extension, presumed political views. There is little room for nuance or civility in a civil war.

The U.N. and other international organizations have said that both sides in the bitter 18-month Syrian conflict are guilty of committing human-rights abuses, although President Bashar Assad’s forces are responsible for the vast majority of the transgressions. In more than a year of clandestine travel in Syria, TIME has seen little direct evidence of rebel attacks on civilians, although suspected shabiha (regime thugs) and loyalist troops are often treated mercilessly.

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However, an FSA fighter told TIME of a rebel attack on Alawite civilians in a village in Sahel al-Ghab, a vast expanse of plains between Idlib and Hama. He said the small group of rebels were in the village to apprehend a suspected shabih, but things didn’t go as planned. He said a woman opened fire on the group, prompting some of the fighters to shoot her dead and then kill two other women and several children in the house. “We had a serious fight. We, the rebels, clashed over the killing of the women and children,” he said. “We told the others it was wrong, forbidden, but some of them didn’t care.”

The fighter was extremely troubled as he recalled the incident. “See this blood?” he said, pointing to a patch on the knees of his jeans. “It’s Alawite blood.” He held his head in his hands, asking God for forgiveness. “What are we becoming?” he said. There was no way to verify his account. He said he and the other men buried the bodies and hurriedly left town before the army arrived. There has been no report of the alleged incident in state media.

The longer the conflict persists, the greater the likelihood that Syria’s diverse social and religious fabric will fray, with hatred and fear becoming a part of everyday life. Already, the local version of cops and robbers is “thuwar (revolutionaries) and shabiha.” Nobody wants to be the shabiha. Child’s play sometimes includes pretending to man a checkpoint and asking passersby for ID. “Are you with the revolution or against?” one child asks as he stands at his front door.

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Death is commonplace. FSA soldiers in the town of Saraqeb in Idlib province say they call ahead to the gravedigger before they head out on a mission, to prepare sites in advance. “Don’t think I want to die,” says Basil, a muscular father of two who sports a Salafi-style beard but enjoys a good whiskey. “People who die now are just numbers. Those with families, their families suffer, nobody helps them. I’ve been fighting for more than a year. I want to live. Do you think I am happy killing Syrians?”

Yet enemies can still easily become friends with a simple switch of allegiance. Defectors are often quickly and warmly embraced by rebels. Barri recalls with fondness an Alawite lieutenant colonel who defected along with his unit about a year ago. Defections are often negotiated over the phone, and Barri says he came to like and respect the Alawite officer. “He was a good man. He didn’t leave us his ammunition when he left, but he was a good man.”

The 20 or so men in Jabal al-Zawya retreat to a room, where a dinner of chicken and rice, grilled mincemeat, eggplant dip, salad and yogurt is spread out on plastic sheets on the floor, as is customary. After dinner they return to the cushions under the almond tree, their weapons at their sides, to enjoy narghiles — what Westerners often refer to as hookahs — exuding sweet apple-scented tobacco into the air, to grapes and soft drinks, tea and coffee, and the intermittent sound of shells thudding in the near and far distance.

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The conversation shifts to the meager distribution of weapons and the random and infrequent payment of salaries to select FSA groups (about $200 — for a married man; $120 for singles; and less than $100 for expenses), as well as the spiraling cost of gasoline (at minimum, $1.70 per liter; up to $2.50 in other areas) and the effect of criminals stealing fuel tankers on the dwindling availability of gasoline. They also wistfully debate when the regime will fall: in 10 days, according to one; Aug. 25, according to another, based on his sister’s dream, although she has not specified the year.

Barri, who took up arms to defend his village, admits the war has changed him. “You know,” he says quietly, “I don’t have a heart anymore. I’ve seen so many things. I saw three of my friends killed, one of them crushed under a government tank. I try to forget sometimes, but I can’t.” In the past five months, he has been wounded three times. He walks with a limp, courtesy of a shrapnel wound to his left leg. The background on his Nokia phone is a picture of his younger brother Ahmad, who was killed on Aug. 10 when the government shelled their hometown.

It was the same day that Barri’s unit took 21 prisoners on the last day of a confrontation at a checkpoint. “Five officers and 21 soldiers. We kept three alive,” he says, “to interrogate them.” Abu Mohammad, an older man with salt-and-pepper hair a shade lighter than his dark-gray galabiya (a loose, floor-length robe) tries to blunt Barri’s remark about the killing of loyalist soldiers. “We have a lot of people who lost brothers, who lost families, so the soldiers were killed,” he says. “If you are a mother, you lost your son, and you find the person who killed him, what would you do to him?”

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Barri pulls out a spiral notebook with an image of three red roses on its cover that his men confiscated from the checkpoint. He opens it to a page divided into two equal columns, with the second column only partially filled. Each line contains a name, sometimes incomplete, as well as a phone number, in red ink. He hands the book to another FSA fighter from a different area of Idlib. “Do you know any of them?” Barri asks, inquiring about the loyalist officers. “They’re all Alawite. They are responsible for massacres in Idlib.” The man peruses the page. “They’re not all Alawite,” he responds.

Barri doesn’t seem to care for the other pages in the notebook, which are full of handwritten poetry. The words could well have been written by one of the men whose dog tags jingle in his pocket, a man who may or may not be alive. On one page, there is a picture drawn in pencil of a high-cheeked woman with hoop earrings, voluminous hair falling around her shoulders. Beside it, the following lines: “Whoever challenges me to love you, I accept that challenge. Whoever challenges me to your love, I will eliminate from the earth.”

The poem was simply signed, “I love you.”

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