Part of Manchester Piccadilly station had to be evacuated after a fire broke out beneath two of the platforms.
The blaze is thought to have started in railway arches near Fairfield Street, which runs under platforms 13 and 14. Fire crews were called at 0640 GMT.
Some train services have been disrupted and others have been terminating at nearby Manchester Oxford Road.
There has also been disruption to road traffic in the area, as Fairfield Street had to be closed.