Videos showed intense clashes between protesters and security forces in the city on Monday night. Repeated gunfire can be heard in the footage, as well as cries and shouts.
Security operatives in Iran have launched a violent crackdown on protesters resulting in the killing of 185 people, including 19 children.
Human rights activists expressed alarm after Security forces fired live rounds indiscriminately at protesters in Iran.
According to Amnesty International, security forces had used firearms indiscriminately in Sanandaj and videos posted by Kurdish human rights group Hengaw show police shooting at homes.
Hengaw reported that at least five civilians had been killed and 400 injured across the region since Sunday, October 9 and warned that the death toll might be higher because authorities were disrupting local internet and mobile networks.
Hengaw reported on Tuesday October 11, that over the past three days, protests had taken place in 10 areas of Kurdistan, Kermanshah and West Azerbaijan provinces, with Sanandaj the epicentre of the unrest and the crackdown by authorities.
Videos showed intense clashes between protesters and security forces in the city on Monday night. Repeated gunfire can be heard in the footage, as well as cries and shouts.
Protests against Iran's Islamic leadership have swept across Iran since the death three weeks ago of Mahsa Amini, a Kurdish woman from the western city of Saqqez who fell into a coma after being detained by morality police in Tehran for allegedly violating the strict hijab law.
The protests are now considered the most serious challenge to the Islamic Republic since its inception in 1979.
Meanwhile Iranian leadership have accused foreign enemies and exiled opposition groups of fomenting "riots" that they will not tolerate.
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