Nottingham station has been evacuated after a large blaze broke out.
Nottinghamshire Fire and Rescue Service sent eight appliances to the scene.
Video posted to social media shows smoke billowing from a building in the early hours.
The fire service tweeted: "The incident at #NottinghamTrainStation is now a large incident with eight appliances in attendance.
"Crews working hard on the scene to resolve this incident - thank you for your patience!"
East Midlands Trains tweeted: "Please do not travel to Nottingham station this morning as trains will be unable to run and we are unable to provide road support to/from the station."
A spokeswoman for East Midlands Ambulance Service said there were no reported casualties.
"We are aware of the incident and, at the minute, there are no reported casualties," she said.
"We have a clinical manager and specialist paramedics at the scene."
An East Midlands Trains spokesman said: "Emergency services have been called to Nottingham station to deal with a fire. The station has been evacuated and there have been no reports of any injuries to customers or staff.
"We will continue to assist the emergency services in any way that we can.
"No trains will be stopping at the station until further notice.
"Our current advice to customers is not to travel to or from Nottingham station this morning.
"Passengers are advised to check www.eastmidlandstrains.co.uk for the latest travel information."