A large explosion rocked Shahid Rajaee port in the southern Iranian city of Bandar Abbas on Saturday, killing at least four people and injuring more than 500.
Hossein Zafari, a spokesperson for Iran's crisis management organisation, appeared to blame the explosion on poor storage of chemicals in containers at Shahid Rajaee.
"The cause of the explosion was the chemicals inside the containers," he told Iran's ILNA news agency.
"Previously, the Director General of Crisis Management had given warnings to this port during their visits and had pointed out the possibility of danger," Zafari said.
An Iranian government spokesperson, however, said that although chemicals had likely caused the blast, it was not yet possible to determine the exact reason.
Oil facilities were not affected by the blast as the National Iranian Petroleum Refining and Distribution Company issued a statement saying: "The explosion and fire in Shahid Rajaee Port have no connection to refineries, fuel tanks, distribution complexes and oil pipelines related to this company."
The large blast shattered windows within a radius of several kilometres, Iranian media said.
Fars news said the blast was heard in Qeshm, an island 26 km (16 miles) south of Bandar Abbas.
Brazil's working class president Lula wins historic fourth term
India to evacuate thousands as Cyclone Arnab nears eastern coast
Large fire breaks out on island off Hong Kong
Jordan arrests 3 over Karak church attack, state TV says
Serbia's Vucic concedes defeat in historic election win for student protest movement
