Iran arrested a prominent former member of its national football team on Thursday over his criticism of the government.
The Tehran authorities have been grappling with nationwide protests for several months that have now cast a shadow over its participation at the World Cup.
Voria Ghafouri was arrested for "insulting the national football team and propagandising against the government," the Fars and Tasnim news agencies reported.
Ghafouri, who was not chosen to go to the World Cup, has been an outspoken critic of Iranian authorities throughout his career.
He objected to a longstanding ban on women spectators at men's football matches as well as Iran's confrontational foreign policy, which has led to crippling Western sanctions.
More recently, he expressed sympathy for the family of Mahsa Amini, a 22-year-old woman whose death while in the custody of Iran's morality police ignited the latest protests.
In recent days he also called for an end to a violent crackdown on protests in Iran's western Kurdistan region.
National team refuses to sing
The reports of his arrest came ahead of Friday's World Cup match between Iran and Wales.
At Iran's opening match, a 6-2 loss to England, the members of the Iranian national team declined to sing along to their national anthem, and some fans expressed support for the protests.
The protests were ignited by the 16 September death of Amini, a Kurdish woman arrested by the morality police in the capital Tehran.
They rapidly escalated into nationwide demonstrations calling for the overthrow of the Islamic Republic.
The western Kurdish region of the country, where both Amini and Ghafouri are from, has been the epicentre of the protests. Shops were closed in the region on Thursday following calls for a general strike.
Iranian officials have not said whether Ghafouri's activism was a factor in not choosing him for the national team. He plays for the Khuzestan Foolad team in the southwestern city of Ahvaz.
The club's chairman, Hamidreza Garshasbi, resigned later on Thursday, the ILNA news agency reported without elaborating.
The protests show no sign of waning and mark one of the biggest challenges to Iran's ruling clerics since the 1979 Islamic Revolution that brought them to power.
Rights groups say security forces have used unleashed live ammunition and birdshot on the protesters, as well as beating and arresting them, with much of the violence captured on video.
At least 442 protesters have been killed and more than 18,000 detained since the start of the unrest, according to Human Rights Activists in Iran, a group that has been monitoring the protests.
Another football star shunned
The UN Human Rights Council voted Thursday to condemn the crackdown and to create an independent fact-finding mission to investigate alleged abuses, particularly those committed against women and children.
Authorities have blamed the unrest on hostile foreign powers without providing evidence and say separatists and other armed groups have attacked security forces.
Human Rights Activists in Iran said at least 57 security personnel had been killed, while state media have reported a higher toll.
The protesters say they are fed up after decades of social and political repression, including a strict dress code imposed on women.
Young women have played a leading role in the protests, stripping off the mandatory Islamic headscarf to express their rejection of clerical rule.
Some Iranians are actively rooting against their own team at the World Cup, associating it with rulers they view as violent and corrupt.
Others insist the national team, which includes players who have spoken out on social media in solidarity with the protests, represents the country's people.
The team's star forward, Sardar Azmoun, who has been vocal about the protests online, was on the bench during the opening match. In addition to Ghafouri, two other former football stars have been arrested for expressing support for the protests.