Bomb-carrying drones targeted an Iranian defence factory in the central city of Isfahan overnight, authorities said early on Sunday.
The Iranian Defence Ministry offered no information on who it suspected carried out the attack, which caused some damage to the plant.
It came amid heightened regional and international tensions engulfing the Islamic Republic.
Elsewhere, a refinery fire broke out in the country's north-west, and a 5.9-magnitude earthquake struck nearby, killing two people.
Tehran has been targeted in suspected Israeli drone strikes amid a shadow war with its Middle East rival as its nuclear deal with world powers collapsed.
Meanwhile, tensions also remain high with neighbouring Azerbaijan after a gunman attacked that country's embassy in Tehran, killing its security chief and injuring two others.
Details on the Isfahan attack, which happened at around 11.30pm on Saturday, remained scarce.
A Defence Ministry statement described three drones being launched at the facility, with two of them successfully shot down.
A third apparently struck the building, causing "minor damage" to its roof, but no-one was injured, the ministry said.