Syrian President Bashar Al-Assad
Syrian President Bashar Al-Assad Reuters

A new report released Monday offers evidence that Syrian government officials committed serious war crimes.

A team of internationally renowned war crimes prosecutors and forensic experts said they found "direct evidence" of "systematic torture and killing" by President Bashar Al-Assad's regime.

The contents of the report were revealed to CNN and The Guardian newspaper. It is based on thousands of photographs of dead bodies of alleged detainees killed in Syrian government custody.

The experts who authored the report say the evidence in the photos would stand up in an international criminal tribunal.

"This is a smoking gun," David Crane, one of the report's authors, told CNN, adding, "Any prosecutor would like this kind of evidence - the photos and the process. This is direct evidence of the regime's killing machine."

Crane, the first chief prosecutor of the Special Court for Sierra Leone, indicted former Liberian President Charles Taylor for war crimes and crimes against humanity. Taylor went on to become the first former head of state convicted of war crimes since World War II. He was sentenced to 50 years in prison.

CNN noted it cannot independently confirm the authenticity of the photographs, documents and testimony referenced in the report, and is relying on the conclusions of the team behind it, which includes international criminal prosecutors, a forensic pathologist, an anthropologist and an expert in digital imaging.

The bodies in the photos showed signs of starvation, brutal beatings, strangulation, and other forms of torture and killing, according to the report.

In a group of photos of 150 individuals examined in detail by the experts, 62% of the bodies showed emaciation - severely low body weight with a hollow appearance indicating starvation. The majority of all of the victims were men most likely aged 20-40.

A complex numbering system was also used to catalog the corpses, with only the relevant intelligence service knowing the identities of the corpses. It was an effort, the report says, to keep track of which security service was responsible for the death, and then later to provide false documentation that the person had died in a hospital.

One of the three lawyers who authored the report, Sir Desmond de Silva, the former chief prosecutor of the Special Court for Sierra Leone, likened the images to those of Holocaust survivors.

The emaciated bodies were the product of starvation as a method of torture, "reminiscent of the pictures of those [who] were found still alive in the Nazi death camps after World War II," he told CNN.

"This evidence could underpin a charge of crimes against humanity -- without any shadow of a doubt," he added. "Of course, it's not for us to make a decision. All we can do is evaluate the evidence and say this evidence is capable of being accepted by a tribunal as genuine."

The report draws its evidence from the testimony of a Syrian government defector codenamed "Caesar" and almost 27,000 photographs he provided. 55,000 such images were brought out of the country, said CNN.

According to the report, Caesar worked as photographer in the military police. Once the war broke out, his work consisted entirely of documenting "killed detainees."

He claimed to have photographed as many as 50 bodies a day.

At one point he took the unusual step of photographing a group of bodies to show that it "looked like a slaughterhouse," according to the report.

The fact that all the bodies were photographed, the report's authors say, strongly suggests that "the killings were systematic, ordered, and directed from above."

"It's a callous, industrial machine grinding its citizens," Crane told CNN. "It is industrial age mass killing."

The killings may have been so thoroughly documented as a way of proving each person's death without allowing the deceased's family to see the body, the report suggests. Also, it may have been aimed at proving that "orders to execute individuals had been carried out."

In addition to de Silva and Crane, the report was co-authored by Professor Sir Geoffrey Nice, former lead prosecutor against former Yugoslav President Slobodan Milosevic.

The report says "Caesar" brought from Syria photographs of thousands of people who had been killed, he says, by the regime.

The lawyers and the three forensics experts with whom they worked were given 26,948 images on a laptop computer. They, in turn, did a "formal analysis" of images of 835 and then a much more detailed examination of 150 individuals.

The images given to CNN show stomachs, faces and even legs that are concave -- sunken, rather than convex. On some torsos, bruising and bleeding is so severe that the victims' skin is a mosaic of black, red, purple and pink.

Oblong and parallel wounds, a mix of bruises and torn skin, line one man's chest and torso, covering every inch of the victim's body from neck to pelvis.

"This is not just somebody who is thin, or who maybe hasn't had enough food because there's a war going on," Dr. Stuart Hamilton, a forensic pathologist who examined the evidence, told CNN. "This is somebody who has been really starved."

The forensics team identified the neck bruising as consistent with strangulation with a rope, piece of rubber, or other such object, as opposed to the marks that would be left by a hanging.

"Strangulation of this kind is also consistent with strangulation being used as a method of torture," the report reads.

CNN noted that Syria is not a member of the International Criminal Court, and that the only way the court could prosecute someone from Syria would be through a referral from the United Nations Security Council.

Because of Russia's support for the Assad regime, and because it has veto power on the council, such a referral seems unlikely, at least for the time being, the network noted.

This is not the first time that a report on Assad’s war crimes has surfaced. In October, a report released by Human Rights Watch (HRW) revealed how the Assad regime used highly powerful bombs to target a high school in the rebel-controlled city of Raqqa. That report was based on satellite imagery.

In December, the United Nations’ High Commissioner for Human Rights, Navi Pillay, said for the first time that war crimes by pro-regime forces in Syria were authorized "at the highest level," including by Assad.

Pillay made the statements based on the findings of a special inquiry into abuses by both sides in the Syrian civil war, and added that "the scale and viciousness of the abuses being perpetrated by elements on both sides almost defies belief."

A recent report by UN inspectors said that chemical weapons have been used at least five times during the Syrian conflict and in some cases children and civilians have been slaughtered.

That report did not, however, attribute blame for the attacks, as this was not part of the mandate given to the team by the UN Security Council.