Assailants on motorbikes shot dead nine people, including a woman and two children, during protests in two separate attacks in southern Iran, state media said on Thursday.
Three suspects were arrested and the hunt was on for others after Wednesday's first attack on protesters and security forces in Izeh, said a senior judicial official in Khuzestan province.
In a separate attack four hours later in Iran's third largest city Isfahan, two assailants on a motorcycle fired automatic weapons at Basij paramilitary force members, killing two and wounding two others, Fars news agency reported.
The attacks occurred as protests over the September 16 death in custody of Mahsa Amini intensified on the third anniversary of bloody unrest over fuel price hikes.
"Two wounded people died at dawn on Thursday, bringing the death toll to seven killed and eight wounded," the official IRNA news agency reported.
The dead included a 45-year-old woman and two children aged nine and 13, said an official at the Jondishapour hospital in Ahvaz, the provincial capital.
Among the eight wounded were two Basij and three police officers, according to a security official interviewed by state television.
"A terrorist group took advantage of a gathering of protesters in front of the central market of the locality to open fire on people and security officers," IRNA said.
Riding two motorcycles, the assailants opened fire at a central market in Izeh at around 5:30 pm (1400 GMT), killing five and wounding 10, Khuzestan's deputy governor for security, Valiollah Hayati, told state television.
It is the second attack that the Iranian authorities have blamed on "terrorists" since nationwide protests flared over Amini's death, after her arrest for allegedly flouting Iran's hijab dress code for women.
Following the shooting in Isfahan, President Ebrahim Raisi ordered the authorities "to act promptly to identify the perpetrators of the attack and hand them over to the justice system for punishment", Fars reported.
On October 26, at least 13 people were killed in an armed attack claimed by the Islamic State group on a Shiite Muslim shrine in the southern city of Shiraz, according to an official toll.