REYHANLI, Turkey -- Three years ago, Abu Ameen’s fleet of trucks regularly crossed the border into Syria with ease, carrying everything from vegetable oil to heavy machinery. But these days, with Syria gripped by war without an end in sight, he’s afraid to dispatch his trucks carrying life-sustaining humanitarian aid because of what he says is a worsening looting problem.

"The refugees are growing wild," said Ameen, a Syrian manager of a large fleet of Turkish and Syrian drivers. "They keep putting up barriers and stealing from the trucks.”

Ameen's fears are increasingly common along the Bab Al Hawa border crossing here, where truck drivers say the delivery of aid has become a perilous, and often impossible, endeavor. About 40 percent of the population in war-ridden Syria is in desperate need of aid, but looting of already scarce resources means that many Syrians aren’t receiving the food, medicine and clothing they need to survive.

Truck drivers waiting along the border, some of whom have traveled more than a month to get here, say the most common good transported to Syria right now is food. They speculate that about half of all the goods consist of humanitarian aid coming from NGOs and aid groups all over the world. The other half, they say, are goods for trading with businessmen across the border: cars, electronics, heavy machinery, building materials. Syrians waiting to cross from Turkey -- on some days, dozens, on others, thousands -- also carry supplies, such as medicine for family members or money for weaponry.

Rumors abound as to who is responsible for the looting. Some Syrians and Turks along the border say extremist rebels are robbing trucks in order to gain control of refugee camps (where aid means power), while others say more moderate rebel groups are capitalizing on a desperate situation. Many, like Ameen, say the refugees themselves are stealing, hungry and desperate for aid that is not evenly distributed. Then there are whispers of Turkish businessmen turned war profiteers, crossing the border to try their hand at black market trade.

"The risk factor right now is astronomical. Much of the aid that has gone in has fallen into different hands," said one aid worker who regularly distributes Western humanitarian aid at refugee camps in Syria. He asked to remain anonymous due to security concerns.

"If you control what's coming through the border, then you can charge ridiculous amounts for a loaf of bread," he said, adding that some of the internally displaced Syrians who are promised resources now have to give money to looters who are selling aid for profit. "You can expand on the actual aid and start a business with that."

The delivery of aid is further complicated by Syrian rebel groups' battle for power of the borders. The Islamic Front -- the largest rebel coalition in Syria -- is widely considered to control the Bab Al Hawa border and the nearby refugee camp, but its power struggle with the Islamic State of Iraq and Syria, an al-Qaeda splinter group, has hindered aid deliveries and endangered the lives of Syrians already fleeing extreme violence.

In the past week, two blasts have targeted strategic border crossings: One hit a hospital near Bab Al Hawa and another detonated in a refugee camp next to Bab Al Salama, another main crossing into northern Syria two and a half hours northwest of Bab Al Hawa. Opposition groups have blamed ISIS for both attacks.

Aid workers and truck drivers must navigate the maze of rebel groups in order to get humanitarian assistance to hard-hit areas and sprawling camps for internally displaced Syrians.

"All aid organisations, whether they admit it or not, have to acquire some extent of relations -- direct or indirect, positive or simply neutral -- with armed groups should they be in control of border crossings or key transport routes," said Charles Lister, a Syria expert and visiting fellow at Brookings Doha Center. "The eruption of infighting between rival groups on the ground would leave aid organisations with a complex balance to find and very likely a dilemma over whether the provision of aid in that area is still feasible."

Fighting between rebel groups over the Bab Al Hawa border crossing has also caused week-long closings of the border in recent months, making it impossible for thousands of trucks to deliver their cargo to Syrian drivers and merchants on the other side. When the border is closed, trucks line the main road leading to Bab Al Hawa for miles and miles.

"We’ve spent 15 days here not making any money," Joma’a, a Turkish man who has been driving trucks for 15 years, said recently after the border closed because of rebel infighting and reports of mass looting. He asked to withhold his last name due to concerns for his safety.

Joma'a only gets paid if his cargo makes it over the border to Syria, where another truck driver or merchant picks it up. He blames the Turkish government -- and those who are looting -- for causing the border to close. Standing in front of a line of trucks double parked for as far as the eye can see, he throws up his arms in anger, purple prayer beads in one hand. As a Turkish armored personnel carrier rolled past, he yelled: "We need to pay rent!"

When the war in Syria first began, Joma’a quit his job as a truck driver, thinking he wouldn’t be able to make enough money to survive since Turkish drivers weren’t allowed across the border for security reasons. But when he couldn’t find other work, Joma’a picked up his route once again. Instead of driving through Syria, he began stopping just before the border and transferring his cargo to Syrian drivers and merchants who would risk their lives to deliver aid.

On Saturday, the U.N. Security Council unanimously agreed on a resolution calling for all parties in the Syrian war to allow for the distribution of aid, while also decrying the use of barrel bombs and al-Qaeda linked terrorist attacks.

"This resolution goes further than we have been able to get in three years," U.S. Ambassador Samantha Power said, according to Reuters. "But a resolution is just words, it is implementation that matters and that's what we're starting measuring right now."

The aid worker who distributes resources to refugee camps said he doubts the resolution will have any real impact on the ground.

"My inbox is full of people all over the world who want to get involved and want to work for Syria," he said, his exhaustion apparent. "But what I don’t like doing is giving them the reality because then they’ll lose interest. [Syria] is at a critical point right now, I believe it can go either way."