Trains between Harrow and central London are being delayed because of a signalling problem.
Southern Trains services between Clapham Junction and Milton Keynes Central, which run through Wembley Central and Harrow & Wealdstone, are being delayed by approximately 30 minutes after a signalling problem near Willesden Junction.
The problem is also causing delays to London Overground services.
Tickets are being accepted on London Underground and London Midland services while work to fix the fault is carried out.
For live traffic and travel updates, click here .
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