One person has been killed and at least 20 hurt in an explosion at a refinery in Iran during a visit by President Mahmoud Ahmadinejad, Iranian media say.
He was not hurt in the blast and went on to make a televised speech to mark the opening of the oil refinery, in the south-western city of Abadan.
A technical problem caused the blast and then a fire, Fars news agency said.
Thick smoke was seen rising from the refinery but the fire was under control, the semi-official agency said.
Another news agency, Mehr, said the explosion was caused by a gas leak.
The refinery is being launched in two phases and ultimately will produce more than 6m litres (1.3m UK gallons) of petrol a day, mostly for domestic consumption.
Correspondents say Mr Ahmadinejad's presence shows the importance Iran, a major oil producer, places on increasing its refining capacity as sanctions hit its ability to import petrol.
The port of Abadan has a special significance in Iranian history after post-war Prime Minister Mohammad Mossadeq nationalised the Iranian assets of the Anglo-Iranian oil company, an action which led eventually to a CIA-backed coup which overthrew him and led to decades of Iranian animosity towards the West.