More firefighters are now at the scene of a fire at a power station on the outskirts of Sheffield.
Crews were called to E.ON Climate and Renewables plant, in Blackburn Meadows at around 3.45am.
Four fire engines from Fire engines from Elm Lane, Tankersley, Rotherham and Central stations were at the scene this morning.
A further three engines are at the site, which is next to the Tinsley Viaduct, this afternoon.
The cause of the fire has not yet been released.