(LONDON) — After dedicating his life to fighting the regime of Assad, Mazen Al-Hamada did not live to see it fall.

A symbol of resilience and courage, the famous Syrian activist was found dead in the “slaughterhouse” prison of Saydnaya in Damascus, as confirmed by the Syrian Emergency Task Force to ABC News.

An unverified photo circulating online shows his disfigured face and suggests he was killed just before the rebels that ousted Assad reached the prison to liberate detainees, according to independent observers.

On Thursday, hundreds gathered in Damascus for Al-Hamada’s funeral, where one of his sisters leading the procession called him “a martyr of revolution and freedom.”

Originally from Deir Ezzor, Al-Hamada was first arrested in 2011 when he organized pro-democracy rallies in the context of the Arab Spring and documented the brutal repression from the Syrian government.

In 2012, he was arrested again for trying to smuggle baby formula into a besieged suburb of Damascus, returning to prison a second time.

He left Syria in 2013 and was granted asylum in the Netherlands a year later.

Once abroad, the world got to know the horrors endured by Al-Hamada, along with thousands of detainees, as he described them to huge crowds of students, policymakers and the press. He did not spare details of the numerous ways in which he had been tortured, reliving his trauma over and over again to raise awareness.

“Mazen poured his heart into every meeting and to anyone he spoke with,” Humanitarian Programs Director at the Syrian Emergency Task Force (SETF) Natalie Larrison, who was on the road with him and became his close friend, told ABC News. As they traveled the United States, meeting everyone who would listen, from congress members in Washington, D.C., to students in Arkansas, Larrison said he was always “in the backseat singing and clapping and jumping up and down.”

Larrison also said Al-Hamada loved American tacos, especially from Taco Bell, and that he told her he was engaged and kept the ring even after his fiancé had been killed while he was in prison the first time.

With every testimony, Al-Hamada quickly became one of the most prominent advocates for Syrian prisoners held by Assad’s regime, at least 157,000 between 2011 and August 2024, including thousands of women and children, according to a report by the Syrian Network for Human Rights (SNHR).

“Mazen was a gentle soul,” Sara Afshar, a friend of Al-Hamada and the director of the 2017 documentary “Syria’s Disappeared” in which he was featured, told ABC News, “A lot of people in his situation would focus on looking after themselves… but everything that motivated him, with an incredible sense of urgency, every second of the day, was how to get the other prisoners out. Because he knew what they were going through.”

Along with thousands of users on social media, Afshar called for justice for Al-Hamada and the other Syrian detainees who are dead or unaccounted for, echoing the words that Al-Hamada himself said in an interview which has been trending on social media since the news of his death.

“I will not rest until I take them to court and get justice,” Al-Hamada said in the interview, his sunken eyes in tears unable to hide the pain behind his words. “Justice for me and my friends who they killed. Even if it costs my life. Bring them to justice, no matter what.”

Al-Hamada returned to Syria four years ago in a shocking move that some people close to him described as the result of his disappointment in the international community. The last time he was active on his WhatsApp was on Feb. 22, 2020, according to the SETF.

“He became discouraged over time because he gave it his all with people promising to help, and nothing changed,” Larrison told ABC News.

Others, including his sister who spoke at his funeral on Thursday, believe the regime promised him safety if he returned to Syria in an attempt to stop his international anti-Assad campaign. She also said they threatened to hurt his family still in Syria.

“The circumstances of Mazen’s death underscore the heavy price borne by those who dared speak out against Assad’s brutal regime,” the Syrian Emergency Task Force said in a statement remembering Al-Hamada.

The Dutch government never commented on his departure, fostering rumors that it failed to support the refugee and his efforts to raise awareness for the Syrian cause.

When asked about Al-Hamada’s legacy, the people who knew him said it would be justice and his contribution to freeing Syria from Assad’s five decadeslong regime.

“Seeing his funeral service today in Damascus is a testimony to what he meant to the Syrian people. His tireless journey has not been for nothing and his legacy will continue to live on in a free Syria, and he will be remembered always for helping his people be free,” Larrison told ABC News.

“We talked about justice and accountability when he recounted the horrors he had experienced. He didn’t want revenge. What he wanted was justice in a court of law,” Afshar told ABC News. “The world failed him and the other disappeared, and now they are dead. But with all the evidence that is being gathered and the work that so many Syrians have done for years, I have hope that there will be justice. That will be Mazen’s legacy.”

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