There is disruption on the Metropolitan Line this morning due to urgent safety checks being carried out on trains.
A fault has been identified on some of the wheels of these trains; as a result, Transport for London (TfL) has introduced a new timetable which sees trains now running every 15 and 30 minutes.
This is causing severe delays between Baker Street and Aldgate and minor delays on the rest of the line.
A TfL statement confirmed engineers are increasing the frequency of safety inspections, and are currently checking over the entire fleet of trains.
These trains - introduced in 2010 - also run on the Circle and Hammersmith & City lines, though no disruptions to those services have been reported as of yet.
Elsewhere, there is no service on the London Overground between Willesden Junction and Watford Junction due to a track fault at Carpenders Park.
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