Drones equipped with explosives targeted an Iranian defense factory in the central city of Isfahan overnight, the Iranian Defense Ministry announced on January 29, causing some damage at the facility.
The Iranian Defense Ministry released few details on the attack and did not say who it suspected was behind it.
Iran has been targeted in the past by suspected Israeli drone strikes. Israeli officials declined to comment on the attack in Isfahan.
The Wall Street Journal later quoted unidentified U.S. officials as saying Israel had carried out the strike.
"This cowardly act was carried out today as part of the efforts made by enemies of the Iranian nation in recent months to make the Islamic republic insecure," Foreign Minister Hossein Amir-Abdollahian said.
In a statement, the Iranian Defense Ministry said three drones had reportedly targeted the facility, with two of them shot down.
A third apparently made it through to strike the building, causing “minor damage” to its roof and wounding no one, the ministry said.
Video footage downloaded on social media showed what appeared to be the moment the drone struck along the Imam Khomeini Expressway that heads northwest out of Isfahan.
The Iranian Defense Ministry described the site as a “workshop” but did not elaborate on what type of work it was engaged in.
Isfahan is located some 350 kilometers south of Tehran. It is home to both a large air base built for its fleet of American-made F-14 fighter jets and its Nuclear Fuel Research and Production Center.
Separately, Iran’s state TV said a fire broke out at an oil refinery in an industrial zone near the northwestern city of Tabriz. It said the cause was not yet known, as it showed footage of firefighters trying to extinguish the blaze.
The attack comes after Iran's Intelligence Ministry in July claimed to have broken up a plot that it said was aiming to target sensitive sites around Isfahan.
Iranian state TV in October broadcast what it claimed to be confessions by alleged members of Komala --a Kurdish opposition party that is exiled from Iran and now operates out of Iraq -- that they planned to target a military aerospace facility in Isfahan after being trained by Israel's Mossad intelligence service.
The incident at Isfahan is the latest attack on Iranian military or nuclear facilities.
Last year, Iran said an engineer was killed and another employee was wounded in an unexplained incident at the Parchin military and weapons development base east of the capital, Tehran. The ministry called it an accident, without providing further details.
Parchin is home to a military base where the International Atomic Energy Agency has said it suspected Iran conducted tests of explosive triggers that could be used in nuclear weapons.
The attack comes with Tehran facing challenges at home and abroad.
The country has witnessed nationwide protests since the September death of Mahsa Amini, a Kurdish-Iranian woman detained by the country's morality police. Its rial currency has plummeted to new lows against the U.S. dollar.
International talks on reviving an accord with world powers have broken down, and now Tehran is reported to have enriched uranium closer than ever to weapons-grade levels.
Meanwhile, Iran continues to arm Russia with the bomb-carrying drones that Moscow uses in attacks in Ukraine on power plants and civilian targets.