The death toll from the massive explosion at Iran’s largest port, Bandar Abbas, has climbed to at least 40, with over 1,200 people injured, state media reported on Sunday, as firefighting efforts continued. The blast, which occurred on Saturday in the Shahid Rajaee section, Iran’s leading container port, caused widespread damage, shattering windows across several kilometres, ripping metal panels off shipping containers, and destroying goods inside, according to state media. The explosion happened while Iran was engaged in a third round of nuclear negotiations with the United States in Oman.

Fires were still breaking out across the affected area by Sunday night, with helicopters and firefighters working to put them out. While chemicals stored at the port are suspected of contributing to the explosion, the exact cause remains unclear. Iran’s Defence Ministry has rejected international reports suggesting the blast was linked to the mishandling of solid missile fuel.

A ministry spokesperson briefed state TV that the reports were "aligned with enemy psyops" and said the area affected by the blast did not have any military cargo.

The Associated Press, quoting British security company Ambrey, reported that the port had received a shipment of sodium perchlorate in March, a chemical used to propel ballistic missiles, and mishandling it might have caused the explosion. Earlier, in January, the Financial Times had reported that two Iranian ships arrived from China carrying enough sodium perchlorate to fuel up to 260 medium-range missiles, helping Tehran rebuild its missile supplies after it launched direct attacks on its rival Israel in 2024.

Thick black smoke billowed over the area on Sunday, with twisted metal and debris scattered around the blast site. By early afternoon, the head of Iran's Red Crescent Society told state media that the fire was 90% under control, and officials confirmed that operations had resumed in the unaffected sections of Shahid Rajaee port.

On Saturday, a spokesperson for the country’s crisis management organisation suggested that the explosion was caused by improper storage of chemicals in containers at Shahid Rajaee, noting that previous warnings had already pointed out the safety risks. Government spokesperson Fatemeh Mohajerani urged people not to jump to conclusions, saying that final findings would be released once investigations are complete.

In recent years, negligence has frequently been cited as the cause behind several deadly accidents affecting Iran’s energy and industrial sectors.

Iran's President Masoud Pezeshkian asked upon arriving in Bandar Abbas on Sunday, "Did we really have to hold the container here for 3-4 months... until we had 120-140 thousand containers stored in this place?"

In 2023, Iran faced several incidents, including refinery fires, a gas explosion at a coal mine, and an emergency repair accident at Bandar Abbas that resulted in the death of one worker. Iran has also attributed some of these incidents to Israel, which has conducted attacks on Iranian soil in recent years, targeting Iran's nuclear program and bombing the country's air defences last year.