A gas leak caused the explosion at a building in the southern Iranian port of Bandar Abbas on Saturday, the semi-official Mehr news agency reported, citing the local fire department chief.
At least one person was killed and 14 injured in the explosion.
"The initial cause of the building accident in Bandar Abbas was a gas leak and buildup, leading to an explosion. This is the initial theory," Mohammad Amin Lyaghat said, in comments broadcast on state television.
Separate incidents were reported elsewhere in Iran on Saturday but media outlets quickly dismissed any connection to an attack or potential sabotage, with tensions high as US President Donald Trump intensifies threats of military strikes against the Islamic republic.
