Again and again, Mazen al-Hamada risked everything to help his fellow Syrians.

In the early days of the Arab Spring uprisings, he marched in the streets and called for the fall of President Bashar al-Assad's brutal regime.

For that, he was repeatedly arrested and tortured in the country's notorious prison system. 

He escaped to the Netherlands in 2013, and spent the next seven years speaking out about the horrors he had both witnessed and endured in prison, hoping to convince world leaders to bring Assad to justice. 

Finally, in 2020, he returned home in desperation hoping he could convince Syrian authorities to liberate those still trapped behind bars, including his own nephew. 

But he was detained immediately upon arrival at the airport in Damascus, and his loved ones never saw or heard from him again — until Tuesday, when his family identified his body in a hospital morgue.

On Thursday, hundreds of Syrians took to the streets of Damascus, some for the first time in over a decade, for Hamada's funeral procession. 

"I got so emotional watching the videos. It's a comfort to see people honouring him like that," British filmmaker Sara Afshar, Hamada's friend, told As It Happens host Nil Kӧksal. 

"They're giving him a funeral of a hero, which is what he is. He is a hero."

WATCH | Hundreds march for Mazen al-Hamada:

Syrians hold funeral for activist found dead after Assad's ouster

Mourners took part in the funeral procession for Syrian activist Mazen al-Hamada in Damascus on Thursday. Hamada, whose body was found by his family in a military hospital this week, was a well-known activist during the Syrian revolution who was repeatedly arrested and tortured. He had escaped to Europe but returned to Syria in 2020 and was again detained upon arrival.

Afshar first met Hamada in the Netherlands in 2016 while researching for her documentary about the regime's crackdown, Syria's Disappeared: The Case Against Assad.

There were no cameras during that first meeting, she said. They just spoke. But she knew immediately that she wanted him to be a focal point of her film. 

"He was incredibly open — more than anyone else that I had spoken to," she said. 

"He was willing to make himself vulnerable, at a great cost to himself. But the reason he wanted to do that was because he really wanted the whole world to hear his story, to hear about what was happening in these prisons, because he wanted the world to act."

But the world, she said, let him down.

For three years after the film's release in 2017, Hamada travelled the world with Afshar, meeting with policy makers and pushing for justice for Assad's victims.

But what they found, she says, were governments ready to look the other way and normalize relations with the regime.

"That makes me really angry, and it made Mazen really angry," she said. "He was, you know, telling people how appalling and monstrous the situation was inside these prisons, and the world was doing nothing about it."

Why he went back

In 2020, Hamada returned to Syria, against the wishes of his loved ones.

He'd been given assurances from the Syrian government that he'd be safe, the Washington Post reports. But, instead, he was detained immediately upon his arrival at the airport in Damascus. 

"We can sit here and think, well, why would he do such a risky thing?" Afshar said. "But, the thing is, he really felt like he had done absolutely everything he could in the West."

After Hamada's arrest, it's unclear what became of him, which is not uncommon in Syria. The United Nations estimates 100,000 people went missing over the course of the 14-year war, many of them arbitrarily detained or forcibly disappeared. 

When rebels ousted Assad this week and started opening the country's prisons, Hamada's loved ones hoped they might be reunited with him.

Instead, they found him dead in a military hospital, his body in a condition that suggested he had only been killed in the past week. 

Chanting in the streets

On Thursday, Syrians carried his casket, draped with the Syrian flag, through the streets of Damascus.

"We will not forget your blood, Mazen," the marchers, many of them young people, chanted outside a mosque while family and friends held funeral prayers inside.

Others chanted: "We will get our revenge, Bashar. We will bring you before the law."

Some of the marchers knew Hamada, and some did not. Many held up black-and-white photos and shouted the names of their own missing loved ones. 

Hamada's brother, Saed, told Reuters that when Assad's government fell, he wished Hamada would be released from prison so he could see what was happening in Syria. 

But, now, he says, his brother is a martyr. 

"After his martyrdom, we feel happy because we paid the price of this freedom with blood," he said.

For some, Thursday's rally and funeral were a symbol of hope for the war-torn country, whose future remains uncertain. 

Many participants said they last protested in Damascus some 13 years ago, before Assad's crackdown on protesters turned the conflict into a full-blown war.

"I could not have imagined going out in a rally in any way, shape or form in Damascus," said Mohammad Kulthum, 32, as he marched in the procession with his mother.

Afshar says it would have meant the world to Hamada to see the spirit of revolution alive again in the streets of Syria. 

"I wish and hope that where he's resting in peace, he can see how they're honouring him, and what he meant to them and to the fight and the campaign for the disappeared, and to what will come — which is the campaign for justice."