One major blaze broke out at a cardboard manufacturing factory in the city of Nazarabad.
Stormy weather in the area caused the fire to spread to 12 nearby units, a local governor said, adding that efforts are underway to bring the blaze under control.
The cause of the fire is not yet known, and there have been no reports of casualties.
Around the same time, another fire was reported near the Montazer Ghaem power plant in the city of Fardis.
The state-run YJC news agency initially released a video that purportedly showed no fire at the facility.
However, Iranian officials later confirmed the report. Hossein Ashouri, head of the Fardis fire department, said the fire began around 8:41 p.m. in a portable cabin next to a waste platform near the power station.
Strong winds caused the flames to spread over approximately 2,000 square meters. Nine additional fire trucks were deployed, and the blaze was brought under control.
Preliminary findings suggest the fire was caused by negligence on the part of the person stationed in the cabin.
Reports of explosion
Iranian officials have denied any link between the fire and the power plant's operation. However, widespread power outages were reported in several areas of the province.
Residents across Alborz Province told Iran International they heard an explosion shortly before 9 p.m., moments before experiencing an earthquake.
Iran’s Seismological Center confirmed that the 4.0-magnitude quake struck at a depth of 8 kilometers near Mahdasht, on the border of Alborz and Tehran provinces.