Zak Kostopoulos, a 33-year-old Greek LGBTQ activist and drag performer, died Friday after a brutal attack in central Athens. Two people have been arrested, but the details surrounding the incident are still unclear.

The attack was reportedly caught on camera, and the video has been shown by several Greek media outlets and shared on social media, but police have not yet confirmed its authenticity to NBC News.

Zak Kostopoulos via Facebook

The footage, which sources say is part of an ongoing investigation, shows someone who appears to be Kostopolous trying to break free from a locked jewelry store by smashing the store’s glass door with a fire extinguisher. It then shows him attempting to crawl out of the store through an opening in the glass while two men can be seen repeatedly kicking him. After laying on the ground, injured, with a crowd surrounding him, the beaten man then stumbles away before being surrounded by police, who appear to forcefully handcuff him. He can then be seen, hands tied behind his back, being carried away on a stretcher.

Kostopoulos died on the way to the hospital, police told the Athens-based news outlet Kathimerini. According to a forensic report that was released on Monday, Kostopoulos’ precise cause of death is inconclusive, though further autopsy results are expected to be released this week.

“[The body] did not bear injuries that justify death,” Nikos Kalogrias, one of the coroners, told Kathimerini. “He has some bruises across his body — small injuries which alone do not cause death — so we continue with further laboratory examinations.”

The owner of the jewelry store and the owner of a nearby business have been arrested and are currently in police custody. They are reportedly the two men seen kicking Kostopoulos in the video footage.

Initial news reports claimed that Kostopoulos had been armed with a knife and was trying to rob the jewelry store, a claim his supporters dispute.

Through a public Facebook post, Greek LGBTQ activist Gregory Vallianatos claimed Kostopoulos went into the jewelry store looking for shelter after a brawl had erupted at a cafe where he was sitting.

In an on-camera interview with Greece's Omnia TV, Anna Paparoussou, the Kostopoulos family’s attorney, appeared to confirm that the attack was caught on camera and credited the footage with bringing the attack to light.

"If the video did not exist, the case might have closed" without any further investigation, according to Paparoussou. She told Omnia TV no witnesses have been willing to testify.

Kostopoulos was a well-known LGBTQ activist in Athens and was committed to raising awareness about HIV through the organization Positive Voice. He was also a popular drag queen, performing under the stage name “Zackie Oh.”

A protest rally was held in his honor Saturday night in Athens, with 500 people in attendance, according to Greek news reports. And his Facebook page has been turned into a memorial, with supporters sharing an outpouring of both love and anger.

“Today Zak Kostopoulos was buried in his parents village in Greece. Unfortunately, the hate, the violence & the intolerance of the Greek society did not die with him,” Emmanouil Athanasiou wrote on Kostopoulos’ memorial page.

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