Iranian authorities on Saturday prevented the family of Mahsa Amini from holding a ceremony to commemorate the first anniversary of her death, confining her father under “house arrest”, as sporadic protests erupted nationwide despite heavy security, reports said.

Mahsa Amimi’s father Amjad was detained early Saturday as he left the family home in the western town of Saqez, and then released after being warned not to hold a memorial service at her graveside, the Kurdistan Human Rights Network (KHRN), 1500tasvir monitor and Norway-based Iran Human Rights (IHR) said.

“Amjad Amini is under house arrest… Security forces are preventing him from visiting his daughter’s grave,” IHR said.

Official news agency IRNA denied the reports of the father’s brief detention and later said security forces had foiled an assassination attempt against him.

Amini, a 22-year-old woman, died on September 16 last year in police custody. The Islamic Republic’s morality police had arrested Amini for not wearing the proper hijab. Huge protests had erupted aftermath with Iranian women publicly burning their headscarves, and cutting off their hair in order to show their solidarity with the victim.