Iranian soccer player Amir Nasr-Azadani is facing execution for "rioting against authorities," according to media reports.

Nasr-Azadani, 26, was arrested last month and convicted of murdering a policeman and two militia members. He was found guilty of "waging war against God," according to Iranian news reports.

Human rights groups have called the allegations a sham.

Nasr-Azadani's supporters fear he could be executed in Shahid Alikhani square in the Iranian city of Isfahan. CNN reported that officials have installed an execution platform in the square.

CNN also verified documents, video, witness testimony, and statements from inside the country suggesting that at least 43 people, including Nasr-Azadani, could face execution.

State media IRNA said the court in Nasr-Azadani's case obtained "video and sufficient documentation that prove he [Nasr-Azadani] is part of an armed group" and that he confessed to his crimes.

Iran executed two prisoners convicted for crimes allegedly committed during the country's ongoing nationwide protests, which began in late September as an outcry against Iran's morality police.

The protests have expanded into one of the most serious challenges to Iran's theocracy since the 1979 Islamic Revolution.

Iran's government for months has been trying to allege, without offering evidence, that foreign countries have fomented the unrest. Protesters say they are angry over the collapse of the economy, heavy-handed policing, and the entrenched power of the country's Islamic clergy.

Sebastian Strandvall, a former teammate of Nasr-Azadani, told Sky News that Nasr-Azadani was likely just standing up for others.

"Knowing Amir's character, he would go to a protest … he and his friends, would stand up for basic rights, for women's rights, of course, because he is the sort of the person who cares about others. But I don't see him doing a war on God or anything," Strandvall said.

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