A "fully developed fire" at Nottingham station has spread to the roof.
Fifty firefighters are tackling the blaze, which broke out in the main concourse of the station.
A spokeswoman for East Midlands Ambulance Service has said the scene was evacuated and no casualties were reported.
Nottinghamshire Fire and Rescue Service tweeted: "There is a fully developed fire in the main concourse of the station - which has spread to the roof.
"Crews are currently working to stop the fire from spreading, thank you for your patience whilst we work to keep you safe!"
The incident has caused delays across the local transport network.
Trains will not be stopping at the station "until further notice" and East Midlands Trains expect disruption to services throughout Friday (January 12).
Police said surrounding roads are closed and warned that buses and trams are also affected.
"Station Street, Carrington Street and Queen's Road have been closed," Nottinghamshire Police tweeted.