On April 26, a major explosion at Shahid Rajaee port – Iran’s largest port - killed at least 70 people and injured over 1000 more. Beyond the official death toll, many migrant workers are also allegedly missing. These migrants are largely internal and are “without papers” or “records”, including employees of Sina Marine and Port Services Development Company which operated the impacted area of the port.

Chemicals at the port are suspected to have caused the explosion, and the BBC reported that a private maritime consultancy believes the affected containers held missile fuel, saying an Iran-flagged shipped had “discharged a shipment of sodium perchlorate” to the port in March. Iran's Defence Ministry has denied reports that the blast may be linked fuel used for missiles.

Iranian officials have blamed the explosion on mislabelling of dangerous cargo and negligence. The company alleged to have imported the material has not yet been named. The CEO of Sina Marine and Port Services Development Company has blamed "a repeated and catastrophic error involving false declarations of hazardous goods".

Later in April, The Guardian reported that Iranian journalists allege a media crackdown following the explosion. Concerns have been voiced over press freedom following criminal charges against media outlets and activists by the Tehran prosecutor’s office.