An explosion occurred at an ammunition factory run by the Iranian Defence Ministry early on Sunday, following an attack by several small aircraft, according to state news agency IRNA.
The Fars news agency published a video of the explosion near Isfahan in central Iran.
According to the Defence Ministry, the attack was of a military nature. Three of the aircraft were destroyed by Iranian defences. No one was injured in the attack, it said.
The damage was minor, the ISNA news agency reported, citing the ministry. So far, Tehran has not given any information on who was responsible for the attack.
Usually, Tehran blames its arch-enemy Israel for drone attacks, which are also often associated with the nuclear negotiations between Iran and the five UN veto powers. Tehran accuses Israel of trying to sabotage them.
Meanwhile, a major fire broke out at an oil processing plant in the north-west of the country. Dozens of firefighters fought the blaze during the night near the provincial capital of Tabris. According to media reports, the cause of the fire is still unclear.
At least one firefighter was injured.
