Greek authorities on Wednesday arrested three vigilantes after video was posted on social media showing them illegally detaining migrants in the northeastern region of Evros, where 18 migrants were found burned to death the previous day amid ongoing raging wildfires.

Two Greeks and a man of Albanian origin were arrested after the publication of a video showing one of the men holding 13 Syrian and Pakistani migrants in a box trailer being pulled by a four-wheel-drive vehicle near Alexandroupolis. The man filming the video boasts of how he "hunted them down" and caught 25 people and blames the migrants—whom he refers to as "pieces"—for the wildfires, urging others to "collect" more border-crossers before "they burn us."

Later on Wednesday, the 13 migrants were arrested on suspicion of arson. The arrested Albanian vigilante—whose name is not given—toldGreek City Times that he "spotted a group of 13 people who were around an object and were trying to set it on fire while holding a balloon that smelled of gasoline."

"I am not a fascist or a racist," he insisted.

Greek Supreme Court Prosecutor Georgia Aldini on Wednesday ordered an investigation into whether the blaze—which has killed at least 20 people including 18 migrants who crossed over the border from Turkey—was an act of arson perpetrated as part of "an organized plan" by xenophobic agitators.

Aldini described the video of the illegal arrests as "a racist delirium of violence, accusing immigrants of 'burning us' and inciting others to racist pogroms, calling on them to organize and imitate him."

Another video posted Wednesday on social media shows the leader of a group of what the Greek news outlet The Press Project described as "headhunters" giving instructions on how to capture migrants.

Lefteris Papayannakis, director of the Greek Council for Refugees, told the Spanish newspaper El País Thursday that "part of the population thinks that the fires are the fault of the migrants and that's why they chase them."

"They function as a militia; they arrest them on their own account and use violence against them," he added.

Vassilis Kerasiotis, director of the NGO HIAS Greece and a lawyer specializing in migration, told the paper that there are numerous anti-migrant militias operating in Greece, and that "there is tolerance on the part of the authorities, that's why they feel they can freely publicize these criminal acts."

"The role of racism and systemic racism in the treatment of asylum-seekers must be confronted."

Far-right parties and politicians like Greek Solution parliamentarian Paris Papadakis—who accused migrants of starting the fire and "obstructing the work of firefighters"—also regularly issue inflammatory proclamations.

Greek Migration Minister Dimitris Kairides published a statement mourning the deaths of the 18 victims and also condemning "the murderous activity of criminal traffickers (and those who facilitate them) and the trade of illegal migration, which is what endangers the lives of many migrants both on land and at sea every day."

Euronewsreported Thursday that firefighters—scores of whom have been injured—are battling at least 99 different fires in Greece, where temperatures have soared to over 105°F.

The Alexandroupolis arrests came on the same day that a group of United Nations experts including Ashwini K.P., the U.N. special rapporteur on special forms of racism, called on Greek authorities to investigate alleged incidents of racist violence against asylum-seekers and other migrants.

The eight experts said they were "particularly concerned" by Greek security forces' failure to provide "prompt and effective" aid to migrants in distress, including by ensuring their safe disembarkation and adequate reception. The experts noted the case of 12 African asylum-seekers—including a 6-month-old infant—who were rounded up by masked men, stripped of their belongings, and forcibly transported to the port of Mytilene on Lesbos earlier this year.

"The violence, which was captured on video—verified, and reported by the media—exposed the racist exclusion and cruelty of Europe's border protection practices," the experts said in a statement. "The past 12 months have been among the deadliest for asylum-seekers, refugees, and migrants of African descent and others on their journeys, particularly along sea and land routes in the Middle East and North Africa region, and in perilous Sahara and Mediterranean crossings."

"While the investigation is ongoing, there is growing evidence of a deliberate and coordinated policy of forcible return and other dehumanizing border control practices by Greece going far beyond deterrence and in contravention of its international obligations," the experts added. "The role of racism and systemic racism in the treatment of asylum-seekers must be confronted within any meaningful review of these practices."

Beatings, rapes, kidnappings, and illegal detentions are just some of the abuses migrants say they have endured in Greece.

Underscoring the experts' claim, a Greek state television broadcaster faced backlash Thursday after she said on air that "the only good news" about the Evros wildfires "is that there were no casualties, except for the poor 18 charred migrants."

Common Dreamsreported last month that a joint analysis by media outlets and the Berlin-based research agency Forensis found that Greek Coast Guard officials lied when they claimed that distressed migrants aboard a vessel carrying hundreds of people that capsized in the Mediterranean Sea in June refused help. Instead, the investigation suggested the Coast Guard's efforts to tow the vessel destabilized it, causing it to capsize and killing an unknown number of migrants.

Amnesty International had previously condemned what it called the "inhumane" treatment of migrants in the wake of Turkish President Recep Tayyip Erdoğan's February 2020 decision to stop asylum-seekers from transiting through Turkey on their way into Greece and other European countries.

Turkey—which hosts more refugees than any other country in the world—has also been criticized for allegedly shooting and torturing asylum-seekers along the Syrian border, and other alleged abuses.

Turkish media reported Thursday that Turkey's Coast Guard rescued 138 migrants in the Aegean Sea after Greek authorities allegedly pushed them back into Turkish territorial waters. This, after scores of other migrants that Turkey said were repelled by Greece were rescued at sea earlier in the week.