Iran explosives factory blast injures 9: authorities
The blast occurred at Sepahan Nargostar Chemical Industries at 4:00 am local time (2330 GMT) due to "unclear reasons still being investigated," said Mansour Shisheforoush, head of the province's crisis management organisation.
Nine factory workers were injured and transferred to hospital, he added.
He said several investigative teams are currently at the scene to determine the cause of the blast.
The plant is located about 45 kilometres (just under 30 miles) northwest of Isfahan city.
The company manufactures "industrial-commercial explosive materials" and was established in 1941, according to its website.
A string of explosions have hit sensitive sites in Iran last year, including alleged sabotage attacks at a nuclear enrichment facility blamed on Israel.