The site of a July 7 explosion at an oxygen factory in Baqershahr, south of Tehran, which killed two people. State media blamed human error. Photo: Mehdi Khanlari/FARS NEWS/AFP

An explosion hit a power plant in the central Iranian province of Isfahan on Sunday, the latest in a string of fires and explosions at military and civilian sites across the couintry.

State news agency IRNA blamed faulty equipment and said there were no casualties.

And in a separate development, Iran has halted the execution of three people linked to deadly November protests sparked by a hike in petrol prices, one of the accused’s lawyers said.

The Isfahan blast was caused by a worn out transformer at the province’s Islamabad thermal power plan, the managing director of Isfahan’s electricity company, Said Mohseni told, the agency.

The facility returned to normal working conditions after about two hours and Isfahan’s power supply was uninterrupted, he added.

Recent fires and explosions include two blasts which rocked Tehran in late June, one near a military site and the other in a health centre, the latter killing 19 people.

Fires or blasts also hit a shipyard in southern Iran last week, a factory south of Tehran with two dead and the Natanz nuclear complex in central Iran earlier this month.

Iranian authorities called the Natanz fire an accident without elaborating and later said they would not reveal the cause, citing security reasons.

The string of fires and explosions have prompted speculation in Iran that they might be the result of sabotage by arch enemy Israel.

The Jewish state accuses the Islamic republic of seeking to acquire a nuclear bomb while Tehran insists its nuclear program is peaceful.

The executions halt followed a campaign on social media. One of the accused’s lawyers, Babak Paknia, said, “We conveyed a request for a retrial to the Supreme Court and they have accepted it. We hope the verdict will be overturned.”

Iran’s judiciary said last week that a court had upheld the death sentence for the three.

It said evidence had been found on their phones of the three setting alight banks, buses and public buildings in November.

The three are Amirhossein Moradi, 26 a phone retailer worker, Said Tamjidi, a 28-year-old student, and Mohammad Rajabi, also 26.

The demonstrations erupted on November 15 after authorities more than doubled fuel prices overnight, exacerbating economic hardship in the sanctions-hit country.

They rocked a handful of cities before spreading to at least 100 urban centres across the Islamic republic.

Petrol pumps were torched, police stations attacked and shops looted before security forces stepped in amid a near-total internet blackout.

A senior Iranian lawmaker said in June that 230 were killed and thousands injured during the protests.

London-based rights group Amnesty International put the number of deaths at 304, and a group of independent UN rights experts said in December that 400 including at least 12 children could have been killed, based on unconfirmed reports.

The United States has claimed that more than 1,000 were killed in the violence.