Iranian state television says security forces have repelled “armed protesters” who tried to take over police stations and military bases.
The report on Monday says 12 people have been killed amid nationwide protests, including 10 during clashes Sunday night.
State TV said: “Some armed protesters tried to take over some police stations and military bases but faced serious resistance from security forces.”
It did not say where the attacks took place.
Some online videos in recent days have purported to show protesters attacking police stations. Other videos have shown protesters peacefully demonstrating and welcoming police.
The protests began Thursday in Mashhad over economic issues and have since expanded to several cities. Hundreds of people have been arrested.