Transport bosses today blamed a software bug for causing several travel apps to report that all Tube lines were closed during rush hour.
Several popular travel apps for smartphones were showing that all London Underground lines, as well as the Overground, were not running.
TfL's social media pages were soon flooded with queries from passengers.
The Tube Map app sent out a notification to users confirming the bug and asking them to report any problems experienced.
The issues began at around 8am, according to reports - one of the busiest times of the day for the capital’s Tube network.
TfL said the issue was reported to web developers and was fixed by 10am, after receiving messages from worried passengers on social media.
Twitter user Lynne Taylor wrote: "All tube lines showing as closed, technical glitch or has something happened?”
The bug spread across several apps as TfL shares its service information with developers, who then use it to feed into their own apps.
According to the BBC, TfL initially said there was no problem with its feed but this soon changed with the firm saying it had been made aware of an issue which would be looked into.
Passengers told to access TfL web pages for "accurate" information.
