Bomb-carrying drones targeted an Iranian defense factory in the central city of Isfahan overnight, authorities said early Sunday, causing some damage at the plant amid heightened regional and international tensions engulfing the Islamic Republic.

The Iranian Defense Ministry offered no information on who it suspected carried out the attack, which came as a refinery fire separately broke out in the country’s northwest and a 5.9-magnitude earthquake struck nearby, killing two people.

However, Tehran has been targeted in suspected Israeli drone strikes amid a shadow war with its Mideast rival as its nuclear deal with world powers collapsed. Meanwhile, tensions also remain high with neighboring Azerbaijan after a gunman attacked that country’s embassy in Tehran, killing its security chief and wounding two others.

Details on the Isfahan attack, which happened around 11:30 p.m. Saturday, remained scarce. A Defense Ministry statement described three drones being launched at the facility, with two of them successfully 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.

Iranian state television’s English-language arm, Press TV, aired mobile phone video apparently showing the moment that drone struck along the busy Imam Khomeini Expressway that heads northeast out of Isfahan, one of several ways for drivers to go to the holy city of Qom and Tehran, Iran’s capital. A small crowd stood gathered, likely drawn by anti-aircraft fire, watching as an explosion and sparks struck a dark building. Those there fled after the strike.

The Defense Ministry only called the site a “workshop,” without elaborating on what it made. Isfahan, some 350 kilometers (215 miles) south of Tehran, 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.

State TV also said the magnitude-5.9 earthquake killed two people and injured some 580 more in rural areas in West Azerbaijan province, damaging buildings in many villages.

Iran and Israel have long been engaged in a shadow war that has included covert attacks on Iranian military and 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.

In April 2021, Iran blamed Israel for an attack on its underground Natanz nuclear facility that damaged its centrifuges.

Israel has not claimed responsibility for the attack, but Israeli media widely reported that the country had orchestrated a devastating cyberattack that caused a blackout at the nuclear facility. Israeli officials rarely acknowledge operations carried out by the country’s secret military units or its Mossad intelligence agency.

In 2020, Iran blamed Israel for a sophisticated attack that killed its top nuclear scientist.

Iran has always insisted its nuclear program is for purely peaceful purposes. U.S. intelligence agencies, Western nations and the International Atomic Energy Agency have said Iran ran an organized nuclear weapons program until 2003.

The United Nations’ top nuclear official, Rafael Mariano Grossi, recently warned that Iran has enough highly enriched uranium to build “several” nuclear weapons if it chooses.

Efforts to revive a 2015 agreement with world powers that placed limits on Iran’s nuclear activities ground to a halt last year. Both the U.S. and Israel have vowed to prevent Iran from ever acquiring nuclear weapons, and neither has ruled out military action.

(AP)