Mahsa Amini's father was detained in Iran on the anniversary of his death

Iranian security forces detained Mahsa Amini’s father Saturday on the one year anniversary of the 22-year-old’s death in their custody, which sparked widespread demonstrations across the country, according to reports.

Amjad Amini was arrested as he left his home in western Iran, according to Norwegian human rights group Hengaw. He was detained for a few hours, and warned not to commemorate the anniversary of his daughter’s death, in an apparent attempt to prevent protestors from gathering at her grave and unleashing a fresh round of protests.

Security forces were seen patrolling the street in Tehran and in western Iran.

Roads to the Aichi cemetery where Mahsa is buried were blocked Saturday and military helicopters hovered overhead, preventing the Amini family from holding a traditional religious ceremony a the young woman’s grave, according to reports.

The Kurdistan Human Rights Network said security forces told Amjad Amini that his family did “not have the right” to leave their home and go to the grave, and should not participate in any commemorations of her death. The family said they wanted to hold a traditional religious ceremony, and had visited the grave on Friday, according to a report.

One of Amini’s uncles, Safa Aeli, was detained in Saqez on Sept. 5 and remains in custody, according to reports.

Unable to protest, some Kurdish areas reportedly held a general strike. Hengaw posted photos and videos online that appeared to show streets largely empty and shops shuttered.

Mahsa was beaten to death after she was arrested by Iranian authorities for not properly wearing a hijab, or head covering, in compliance with Iranian law.

Amini’s death sparked more than a month of protests last year throughout the country, some escalating to massive riots as demonstrators openly clashed with security forces in what some experts said nearly led to the collapse of the fundamentalist regime.

In August, the commander-in-chief of the Islamic Revolutionary Guard Corps (IRGC), Hossein Salami, called the protests “the strongest, most dangerous, and most serious” demonstrations in the regime’s history, according to a report in the Jerusalem Post.

The protests were notable for the participation of women, many of whom openly defied the strict dress codes that require hair covering, including hundreds who burned their head coverings and cut their hair in public.

One sign of the impact they had came when the Iranian regime in December claimed to shut down its “morality police” in response.

On Friday, the US imposed new sanctions against Iran.

The U.S. said it was sanctioning 29 people and entities in Iran including members of Iran’s Islamic Revolutionary Guard Corps, the head of Iran’s Prisons Organization and three state-backed media outlets. It also announced visa restrictions on 13 Iranian officials.