Commuter travelling on the Metropolitan line between Harrow on the Hill and Watford have been facing severe delays this morning, November 8.
It's due to an earlier signal failure at North Harrow. The Metropolitan assured commuters that work was being carried out to fix the failure.
The Metropolitan line has updated passengers saying that trains are now running with minor delays on all lines.
At one point, traffic was queuing back to the M40.
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