DUBAI, United Arab Emirates (AP) Gunmen opened fire Wednesday at a major Shiite holy site in the southern city of Shiraz, killing at least 15 people and wounding dozens, according to state-run media.

The official website of the judiciary says two gunmen were arrested and a third is on the run after the attack on the Shah Cheragh mosque. The state-run IRNA news agency reported the death toll and state TV said 40 people were wounded.

The attack, which bore the hallmarks of Sunni extremists who have targeted the countrys Shiite majority in the past, comes as Iran has been convulsed by over a month of anti-government demonstrations, the biggest challenge to the Islamic Republic in over a decade.

Thousands of protesters poured into the streets of a northwestern city to mark the watershed 40 days since the death in custody of 22-year-old Mahsa Amini, whose tragedy sparked the protests.

Deaths are commemorated in Shiite Islam as in many other traditions again 40 days later, typically with an outpouring of grief. In Aminis Kurdish hometown of Saqez, the birthplace of the nationwide unrest now roiling Iran, crowds snaked through the local cemetery and thronged her grave.

Death to the dictator! protesters cried, according to video footage that corresponds with known features of the city and Aichi Cemetery. Women ripped off their headscarves, or hijabs, and waved them above their heads. Other videos showed a massive procession making its way along a highway and through a dusty field toward Aminis grave. There were reports of road closures in the area.

State-linked media reported 10,000 protesters in the procession to her grave.

Hengaw, a Kurdish human rights group, said security forces fired tear gas to disperse demonstrators. The semiofficial ISNA news agency said security forces fired pellets at crowds of demonstrators on the outskirts of Saqez and pushed back demonstrators who tried to attack the governors office. It said local internet access was cut off due to security considerations.