Passengers were evacuated from the new Elizabeth Line at Paddington Station two hours after its long-awaited opening on Tuesday morning due to a fire alert.
Hundreds of rush hour commuters were moved from platforms shortly before 9am while the station was closed to investigate the incident.
A Transport for London spokesperson confirmed that the alert was a false alarm and the station is now open again.
The brief closure followed a smooth launch at 6:20am, when the station's doors opened to around 300 train enthusiasts who had been queuing outside the station.
The first train departed on time at 6.33am carrying hundreds of excited passengers.
It followed a four year delay, after Crossrail suffered numerous issues including construction difficulties and complications installing signalling systems.
It was due to be completed in December 2018 and was set a budget of £14.8 billion in 2010. The final total cost has been estimated at £18.9 billion, including £5.1 billion from the government.
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