The father of Mahsa Amini has been briefly detained, human rights groups say, amid a heavy security force presence on the first anniversary of his daughter's death in Iranian police custody, which sparked months of anti-government protests.
Amjad Amini was warned against marking the anniversary of his daughter's death before being released, the Kurdistan Human Rights Network said.
Iran's official IRNA news agency denied that Amjad Amini was arrested, but it did not say if he was briefly detained or warned.
Earlier, social media and reports by rights groups spoke of security forces taking up positions around Amini's home in Saqez, in western Iran.
The death of the 22-year-old Kurdish woman in the custody of the morality police last year for allegedly flouting the Islamic Republic's mandatory dress code triggered months of protests that represented the biggest show of opposition to the authorities in years.
Many called for an end to more than four decades of Shi'ite clerical rule.
According to social media posts, Amini's parents had said in a statement earlier this week that, despite government warnings, they would hold a "traditional and religious anniversary ceremony" at their 22-year-old daughter's grave in Saqez.
A massive security force presence was deployed in Iran's mostly Kurdish areas on Saturday in anticipation of unrest, according to human rights groups.
Widespread strikes were also reported in multiple cities in Iran's Kurdistan region.
However, IRNA said Amini's hometown of Saqez was "completely quiet" and that calls for strike in Kurdish areas had failed due to "people's vigilance and the presence of security and military forces".
It quoted an official in the Kurdistan province as saying: "A number of agents affiliated with counter-revolutionary groups who had planned to create chaos and prepare media fodder were arrested in the early hours of this morning."
In the protests that followed Amini's death more than 500 people, including 71 minors, were killed, hundreds injured and thousands arrested, rights groups said.
Iran carried out seven executions linked to the unrest.
In a report last month, Amnesty International said Iranian authorities "have been subjecting victims' families to arbitrary arrest and detention, imposing cruel restrictions on peaceful gatherings at grave sites, and destroying victims' gravestones".
Many journalists, lawyers, activists, students, academics, artists, public figures and members of ethnic minorities accused of links with the protest wave, as well as relatives of protesters killed in the unrest, have been arrested, summoned, threatened or fired from jobs in the past few weeks, according to Iranian and Western human rights groups.
Iran's Etemad daily reported in August that the lawyer for Amini's family also faced charges of "propaganda against the system".
If convicted, Saleh Nikbakht faces a jail sentence of between one and three years.